Add Rails backend: accounts via magic link, server documents, sharing

The app becomes a Rails 8 application; the Vue frontend moves to
app/frontend and is served through vite_rails.

- Without an account documents stay in the browser (IndexedDB). Sign-in
  is by magic link or the 6-digit code from the same mail; afterwards
  local documents can be uploaded into the account.
- Server documents (/d/<id>) with versioned saves and a single-editor
  lock per browser tab; others see them read-only and follow by polling.
- Sharing via link (works without an account) and via e-mail invitation,
  roles viewer/editor; the owner manages links and people.
- Store gains a read-only mode that blocks all content changes.
- Solid Queue, Cache and Cable share the one PostgreSQL database.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

db/migrate/20260928120000_create_core_tables.rb

@@ -0,0 +1,71 @@
+class CreateCoreTables < ActiveRecord::Migration[8.1]
+  def change
+    enable_extension "citext"
+    enable_extension "pgcrypto"
+
+    create_table :users do |t|
+      t.citext :email, null: false, index: { unique: true }
+      t.string :display_name
+      t.string :color
+      t.datetime :last_seen_at
+      t.timestamps
+    end
+
+    create_table :sessions do |t|
+      t.references :user, null: false, foreign_key: { on_delete: :cascade }
+      t.string :user_agent
+      t.string :ip_address
+      t.datetime :last_active_at
+      t.timestamps
+    end
+
+    create_table :documents, id: :uuid do |t|
+      t.references :owner, null: false, foreign_key: { to_table: :users, on_delete: :cascade }
+      t.string :title, null: false
+      t.text :content, null: false # the DocumentState JSON, same as inside a .num file
+      t.integer :version, null: false, default: 1
+      t.references :updated_by, foreign_key: { to_table: :users, on_delete: :nullify }
+      t.datetime :content_updated_at, null: false
+      # simple edit lock until live collaboration exists (concept, phase 3)
+      t.string :lock_holder
+      t.string :lock_holder_name
+      t.datetime :lock_expires_at
+      t.timestamps
+    end
+
+    create_table :share_links do |t|
+      t.references :document, type: :uuid, null: false, foreign_key: { on_delete: :cascade }
+      t.integer :role, null: false
+      t.string :token, null: false, index: { unique: true }
+      t.references :created_by, null: false, foreign_key: { to_table: :users, on_delete: :cascade }
+      t.datetime :revoked_at
+      t.timestamps
+    end
+
+    create_table :document_memberships do |t|
+      t.references :document, type: :uuid, null: false, foreign_key: { on_delete: :cascade }
+      t.references :user, null: false, foreign_key: { on_delete: :cascade }
+      t.integer :role, null: false
+      t.integer :source, null: false
+      t.references :share_link, foreign_key: { on_delete: :cascade }
+      t.datetime :last_opened_at
+      t.timestamps
+      t.index [ :document_id, :user_id ], unique: true
+    end
+
+    create_table :magic_links do |t|
+      t.citext :email, null: false, index: true
+      t.string :token_digest, null: false, index: { unique: true }
+      t.string :code_digest, null: false
+      t.integer :purpose, null: false, default: 0
+      t.references :document, type: :uuid, foreign_key: { on_delete: :cascade }
+      t.integer :role
+      t.references :invited_by, foreign_key: { to_table: :users, on_delete: :cascade }
+      t.string :return_to
+      t.integer :failed_attempts, null: false, default: 0
+      t.datetime :expires_at, null: false
+      t.datetime :used_at
+      t.timestamps
+    end
+  end
+end

db/migrate/20260928120100_create_solid_queue_tables.rb

@@ -0,0 +1,164 @@
+# Solid Queue lives in the main database (same as the app data),
+# converted from the generated db/queue_schema.rb.
+class CreateSolidQueueTables < ActiveRecord::Migration[8.1]
+  def change
+    create_table "solid_queue_blocked_executions" do |t|
+      t.bigint "job_id", null: false
+      t.string "queue_name", null: false
+      t.integer "priority", default: 0, null: false
+      t.string "concurrency_key", null: false
+      t.datetime "expires_at", null: false
+      t.datetime "created_at", null: false
+      t.index [ "concurrency_key", "priority", "job_id" ], name: "index_solid_queue_blocked_executions_for_release"
+      t.index [ "expires_at", "concurrency_key" ], name: "index_solid_queue_blocked_executions_for_maintenance"
+      t.index [ "job_id" ], name: "index_solid_queue_blocked_executions_on_job_id", unique: true
+    end
+
+    create_table "solid_queue_claimed_executions" do |t|
+      t.bigint "job_id", null: false
+      t.bigint "process_id"
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_claimed_executions_on_job_id", unique: true
+      t.index [ "process_id", "job_id" ], name: "index_solid_queue_claimed_executions_on_process_id_and_job_id"
+    end
+
+    create_table "solid_queue_failed_executions" do |t|
+      t.bigint "job_id", null: false
+      t.text "error"
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_failed_executions_on_job_id", unique: true
+    end
+
+    create_table "solid_queue_jobs" do |t|
+      t.string "queue_name", null: false
+      t.string "class_name", null: false
+      t.text "arguments"
+      t.integer "priority", default: 0, null: false
+      t.string "active_job_id"
+      t.datetime "scheduled_at"
+      t.datetime "finished_at"
+      t.string "concurrency_key"
+      t.datetime "created_at", null: false
+      t.datetime "updated_at", null: false
+      t.bigint "batch_id"
+      t.index [ "active_job_id" ], name: "index_solid_queue_jobs_on_active_job_id"
+      t.index [ "batch_id" ], name: "index_solid_queue_jobs_on_batch_id"
+      t.index [ "class_name" ], name: "index_solid_queue_jobs_on_class_name"
+      t.index [ "finished_at" ], name: "index_solid_queue_jobs_on_finished_at"
+      t.index [ "queue_name", "finished_at" ], name: "index_solid_queue_jobs_for_filtering"
+      t.index [ "scheduled_at", "finished_at" ], name: "index_solid_queue_jobs_for_alerting"
+    end
+
+    create_table "solid_queue_pauses" do |t|
+      t.string "queue_name", null: false
+      t.datetime "created_at", null: false
+      t.index [ "queue_name" ], name: "index_solid_queue_pauses_on_queue_name", unique: true
+    end
+
+    create_table "solid_queue_processes" do |t|
+      t.string "kind", null: false
+      t.datetime "last_heartbeat_at", null: false
+      t.bigint "supervisor_id"
+      t.integer "pid", null: false
+      t.string "hostname"
+      t.text "metadata"
+      t.datetime "created_at", null: false
+      t.string "name", null: false
+      t.index [ "last_heartbeat_at" ], name: "index_solid_queue_processes_on_last_heartbeat_at"
+      t.index [ "name", "supervisor_id" ], name: "index_solid_queue_processes_on_name_and_supervisor_id", unique: true
+      t.index [ "supervisor_id" ], name: "index_solid_queue_processes_on_supervisor_id"
+    end
+
+    create_table "solid_queue_ready_executions" do |t|
+      t.bigint "job_id", null: false
+      t.string "queue_name", null: false
+      t.integer "priority", default: 0, null: false
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_ready_executions_on_job_id", unique: true
+      t.index [ "priority", "job_id" ], name: "index_solid_queue_poll_all"
+      t.index [ "queue_name", "priority", "job_id" ], name: "index_solid_queue_poll_by_queue"
+    end
+
+    create_table "solid_queue_recurring_executions" do |t|
+      t.bigint "job_id", null: false
+      t.string "task_key", null: false
+      t.datetime "run_at", null: false
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_recurring_executions_on_job_id", unique: true
+      t.index [ "task_key", "run_at" ], name: "index_solid_queue_recurring_executions_on_task_key_and_run_at", unique: true
+    end
+
+    create_table "solid_queue_recurring_tasks" do |t|
+      t.string "key", null: false
+      t.string "schedule", null: false
+      t.string "command", limit: 2048
+      t.string "class_name"
+      t.text "arguments"
+      t.string "queue_name"
+      t.integer "priority", default: 0
+      t.boolean "static", default: true, null: false
+      t.text "description"
+      t.datetime "created_at", null: false
+      t.datetime "updated_at", null: false
+      t.index [ "key" ], name: "index_solid_queue_recurring_tasks_on_key", unique: true
+      t.index [ "static" ], name: "index_solid_queue_recurring_tasks_on_static"
+    end
+
+    create_table "solid_queue_scheduled_executions" do |t|
+      t.bigint "job_id", null: false
+      t.string "queue_name", null: false
+      t.integer "priority", default: 0, null: false
+      t.datetime "scheduled_at", null: false
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_scheduled_executions_on_job_id", unique: true
+      t.index [ "scheduled_at", "priority", "job_id" ], name: "index_solid_queue_dispatch_all"
+    end
+
+    create_table "solid_queue_semaphores" do |t|
+      t.string "key", null: false
+      t.integer "value", default: 1, null: false
+      t.datetime "expires_at", null: false
+      t.datetime "created_at", null: false
+      t.datetime "updated_at", null: false
+      t.index [ "expires_at" ], name: "index_solid_queue_semaphores_on_expires_at"
+      t.index [ "key", "value" ], name: "index_solid_queue_semaphores_on_key_and_value"
+      t.index [ "key" ], name: "index_solid_queue_semaphores_on_key", unique: true
+    end
+
+    create_table "solid_queue_batches" do |t|
+      t.string "active_job_batch_id"
+      t.string "description"
+      t.text "on_finish"
+      t.text "on_success"
+      t.text "on_failure"
+      t.text "metadata"
+      t.integer "total_jobs", default: 0, null: false
+      t.integer "completed_jobs", default: 0, null: false
+      t.integer "failed_jobs", default: 0, null: false
+      t.datetime "enqueued_at"
+      t.datetime "finished_at"
+      t.datetime "failed_at"
+      t.datetime "created_at", null: false
+      t.datetime "updated_at", null: false
+      t.index [ "active_job_batch_id" ], name: "index_solid_queue_batches_on_active_job_batch_id", unique: true
+      t.index [ "finished_at" ], name: "index_solid_queue_batches_on_finished_at"
+    end
+
+    create_table "solid_queue_batch_executions" do |t|
+      t.bigint "job_id", null: false
+      t.bigint "batch_id", null: false
+      t.datetime "created_at", null: false
+      t.index [ "job_id" ], name: "index_solid_queue_batch_executions_on_job_id", unique: true
+      t.index [ "batch_id" ], name: "index_solid_queue_batch_executions_on_batch_id"
+    end
+
+    add_foreign_key "solid_queue_batch_executions", "solid_queue_batches", column: "batch_id", on_delete: :cascade
+    add_foreign_key "solid_queue_batch_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_blocked_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_claimed_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_failed_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_ready_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_recurring_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+    add_foreign_key "solid_queue_scheduled_executions", "solid_queue_jobs", column: "job_id", on_delete: :cascade
+  end
+end

db/migrate/20260928120200_create_solid_cache_tables.rb

@@ -0,0 +1,16 @@
+# Solid Cache lives in the main database (same as the app data),
+# converted from the generated db/cache_schema.rb.
+class CreateSolidCacheTables < ActiveRecord::Migration[8.1]
+  def change
+    create_table "solid_cache_entries" do |t|
+      t.binary "key", limit: 1024, null: false
+      t.binary "value", limit: 536870912, null: false
+      t.datetime "created_at", null: false
+      t.integer "key_hash", limit: 8, null: false
+      t.integer "byte_size", limit: 4, null: false
+      t.index ["byte_size"], name: "index_solid_cache_entries_on_byte_size"
+      t.index ["key_hash", "byte_size"], name: "index_solid_cache_entries_on_key_hash_and_byte_size"
+      t.index ["key_hash"], name: "index_solid_cache_entries_on_key_hash", unique: true
+    end
+  end
+end

db/migrate/20260928120300_create_solid_cable_tables.rb

@@ -0,0 +1,14 @@
+# Solid Cable lives in the main database (same as the app data),
+# converted from the generated db/cable_schema.rb.
+class CreateSolidCableTables < ActiveRecord::Migration[8.1]
+  def change
+    create_table "solid_cable_messages" do |t|
+      t.binary "channel", limit: 1024, null: false
+      t.binary "payload", limit: 536870912, null: false
+      t.datetime "created_at", null: false
+      t.integer "channel_hash", limit: 8, null: false
+      t.index ["channel_hash"], name: "index_solid_cable_messages_on_channel_hash"
+      t.index ["created_at"], name: "index_solid_cable_messages_on_created_at"
+    end
+  end
+end