fix(telegram-calendar-bot): fix dependency version and type error

- Update @nestjs/config from ^10.0.0 to ^3.3.0 (correct version)
- Fix formatStatusMessage to accept null username parameter
- Add pnpm-lock.yaml for reproducible builds

https://claude.ai/code/session_01LwmhvhKpEsvVtY1ZKhYu6f

services/telegram-calendar-bot/package.json

@@ -20,7 +20,7 @@
 	},
 	"dependencies": {
 		"@nestjs/common": "^10.4.15",
-		"@nestjs/config": "^10.0.0",
+		"@nestjs/config": "^3.3.0",
 		"@nestjs/core": "^10.4.15",
 		"@nestjs/platform-express": "^10.4.15",
 		"@nestjs/schedule": "^4.1.2",

services/telegram-calendar-bot/src/bot/formatters.ts

@@ -351,7 +351,7 @@ export function formatHelpMessage(): string {
  */
 export function formatStatusMessage(
 	isLinked: boolean,
-	username?: string,
+	username?: string | null,
 	lastActive?: Date
 ): string {
 	if (!isLinked) {