feat: internal page links and mentions (#604)

* Work on mentions

* fix: properly parse page slug

* fix editor suggestion bugs

* mentions must start with whitespace

* add icon to page mention render

* feat: backlinks - WIP

* UI - WIP

* permissions check
* use FTS for page suggestion

* cleanup

* WIP

* page title fallback

* feat: handle internal link paste

* link styling

* WIP

* Switch back to LIKE operator for search suggestion

* WIP
* scope to workspaceId
* still create link for pages not found

* select necessary columns

* cleanups

apps/server/src/database/migrations/20241218T223249-backlinks.ts

@@ -0,0 +1,33 @@
+import { type Kysely, sql } from 'kysely';
+
+export async function up(db: Kysely<any>): Promise<void> {
+  await db.schema
+    .createTable('backlinks')
+    .addColumn('id', 'uuid', (col) =>
+      col.primaryKey().defaultTo(sql`gen_uuid_v7()`),
+    )
+    .addColumn('source_page_id', 'uuid', (col) =>
+      col.references('pages.id').onDelete('cascade').notNull(),
+    )
+    .addColumn('target_page_id', 'uuid', (col) =>
+      col.references('pages.id').onDelete('cascade').notNull(),
+    )
+    .addColumn('workspace_id', 'uuid', (col) =>
+      col.references('workspaces.id').onDelete('cascade').notNull(),
+    )
+    .addColumn('created_at', 'timestamptz', (col) =>
+      col.notNull().defaultTo(sql`now()`),
+    )
+    .addColumn('updated_at', 'timestamptz', (col) =>
+      col.notNull().defaultTo(sql`now()`),
+    )
+    .addUniqueConstraint('backlinks_source_page_id_target_page_id_unique', [
+      'source_page_id',
+      'target_page_id',
+    ])
+    .execute();
+}
+
+export async function down(db: Kysely<any>): Promise<void> {
+  await db.schema.dropTable('backlinks').execute();
+}