chore: fix lint errors and reduce warnings across codebase (#234)

* chore: fix lint errors and reduce warnings across codebase

- Fix noExplicitAny catches in backend routes and plugins
- Fix noNestedTernary issues in backend services
- Add keyboard event handlers for useKeyWithClickEvents in frontend
- Disable noImportantStyles rule in biome.json
- Fix formatting errors across all changed files
- Fix test file lint issues

Closes #233

* fix: restore any types in test files for TS compatibility

* fix: revert Auth.tsx dependency array changes that caused infinite re-render

* fix: null-safe user.username access in AppContext dependency array

backend/src/db/migrate.ts

@@ -41,8 +41,8 @@ export async function executeMigration(
 		const executed = Number(tables.rows[0].count) || 0;
 
 		return { success: true, executed, errors };
-	} catch (err: any) {
-		errors.push(err.message);
+	} catch (err: unknown) {
+		errors.push((err as Error).message);
 		return { success: false, executed: 0, errors };
 	}
 }