feat: implement full-text search functionality with API integration, add search router and persistence logic, and create related schemas and tests

thoughts-backend/migration/src/lib.rs

@@ -7,6 +7,7 @@ mod m20250906_130237_add_tags;
 mod m20250906_134056_add_api_keys;
 mod m20250906_145148_add_reply_to_thoughts;
 mod m20250906_145755_add_visibility_to_thoughts;
+mod m20250906_231359_add_full_text_search;
 
 pub struct Migrator;
 
@@ -21,6 +22,7 @@ impl MigratorTrait for Migrator {
             Box::new(m20250906_134056_add_api_keys::Migration),
             Box::new(m20250906_145148_add_reply_to_thoughts::Migration),
             Box::new(m20250906_145755_add_visibility_to_thoughts::Migration),
+            Box::new(m20250906_231359_add_full_text_search::Migration),
         ]
     }
 }

thoughts-backend/migration/src/m20250906_231359_add_full_text_search.rs

@@ -0,0 +1,48 @@
+use sea_orm_migration::prelude::*;
+
+#[derive(DeriveMigrationName)]
+pub struct Migration;
+
+#[async_trait::async_trait]
+impl MigrationTrait for Migration {
+    async fn up(&self, manager: &SchemaManager) -> Result<(), DbErr> {
+        // --- Users Table ---
+        // Add the tsvector column for users
+        manager.get_connection().execute_unprepared(
+            "ALTER TABLE \"user\" ADD COLUMN \"search_document\" tsvector \
+            GENERATED ALWAYS AS (to_tsvector('english', username || ' ' || coalesce(display_name, ''))) STORED"
+        ).await?;
+        // Add the GIN index for users
+        manager.get_connection().execute_unprepared(
+            "CREATE INDEX \"user_search_document_idx\" ON \"user\" USING GIN(\"search_document\")"
+        ).await?;
+
+        // --- Thoughts Table ---
+        // Add the tsvector column for thoughts
+        manager
+            .get_connection()
+            .execute_unprepared(
+                "ALTER TABLE \"thought\" ADD COLUMN \"search_document\" tsvector \
+            GENERATED ALWAYS AS (to_tsvector('english', content)) STORED",
+            )
+            .await?;
+        // Add the GIN index for thoughts
+        manager.get_connection().execute_unprepared(
+            "CREATE INDEX \"thought_search_document_idx\" ON \"thought\" USING GIN(\"search_document\")"
+        ).await?;
+
+        Ok(())
+    }
+
+    async fn down(&self, manager: &SchemaManager) -> Result<(), DbErr> {
+        manager
+            .get_connection()
+            .execute_unprepared("ALTER TABLE \"user\" DROP COLUMN \"search_document\"")
+            .await?;
+        manager
+            .get_connection()
+            .execute_unprepared("ALTER TABLE \"thought\" DROP COLUMN \"search_document\"")
+            .await?;
+        Ok(())
+    }
+}