Enable restrict-template-expressions linting rule (#7181)

* [AI] Promote typescript/restrict-template-expressions to error and fix violations

Convert the oxlint rule from "warn" to "error" and fix all 42 violations
by wrapping non-string template expressions with String(). This ensures
type safety in template literals across the codebase.

https://claude.ai/code/session_01Uk8SwFbD6HuUuo3SSMwU9z

* Add release notes for PR #7181

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

packages/sync-server/bin/actual-server.js

@@ -91,12 +91,12 @@ if (values.config) {
 
   if (!configExists) {
     console.log(
-      `Please specify a valid config path. The path ${values.config} does not exist.`,
+      `Please specify a valid config path. The path ${String(values.config)} does not exist.`,
     );
 
     process.exit();
   } else {
-    console.log(`Loading config from ${values.config}`);
+    console.log(`Loading config from ${String(values.config)}`);
     const configJson = JSON.parse(readFileSync(values.config, 'utf-8'));
     process.env.ACTUAL_CONFIG_PATH = values.config;
     setupDataDir(configJson.dataDir);

packages/sync-server/src/util/middlewares.ts

@@ -55,7 +55,7 @@ const requestLoggerMiddleware = expressWinston.logger({
       const { timestamp, level, meta } = args;
       const { res, req } = meta as { res: Response; req: Request };
 
-      return `${timestamp} ${level}: ${req.method} ${res.statusCode} ${req.url}`;
+      return `${String(timestamp)} ${String(level)}: ${req.method} ${res.statusCode} ${req.url}`;
     }),
   ),
 });