Enhance SQLite database initialization in sqliteDb.js

- Added checks to ensure the SQLite database file exists before opening, improving resilience during container startup.
- Implemented error handling for file accessibility, providing clearer error messages if the database file is not readable or writable.

Made-with: Cursor

backend/db/sqliteDb.js

@@ -20,6 +20,21 @@ function getDbPath() {
   if (!fs.existsSync(dir)) {
     fs.mkdirSync(dir, { recursive: true });
   }
+
+  // Ensure the file exists before better-sqlite3 opens it.
+  // This makes container startup resilient when SQLITE_PATH points to
+  // a persistent volume and database file is not created yet.
+  if (!fs.existsSync(p)) {
+    fs.closeSync(fs.openSync(p, 'a'));
+  }
+
+  try {
+    fs.accessSync(p, fs.constants.R_OK | fs.constants.W_OK);
+  } catch (err) {
+    const details = err && err.message ? err.message : String(err);
+    throw new Error(`SQLite file is not readable/writable at "${p}": ${details}`);
+  }
+
   return p;
 }