feat(01-02): add /ready endpoint with database connectivity check

- Add GET /ready endpoint that checks database connection
- Returns 200 'ready' when connected, 503 when not
- Update Routes to require DataSource dependency
- Provide dataSourceLayer in Main.scala
- Use 'hikari' prefix for HikariCP config to avoid ZIO config conflict

summercms/src/db/QuillContext.scala

@@ -27,11 +27,12 @@ object QuillContext {
 
   /** DataSource layer from HikariCP configuration
     *
-    * Reads configuration from "database" prefix in application.conf.
+    * Reads configuration from "hikari" prefix in application.conf.
+    * Uses separate prefix from "database" to avoid conflict with ZIO config.
     * HikariCP manages the connection pool.
     */
   val dataSourceLayer: ZLayer[Any, Throwable, DataSource] =
-    Quill.DataSource.fromPrefix("database")
+    Quill.DataSource.fromPrefix("hikari")
 
   /** Quill PostgreSQL context with snake_case naming
     *