fix: resolve login error handling issues

- Fix translation service to load locales from correct path (src/locales)
- Improve login security to return generic error message for both invalid email and wrong password
- Make frontend error handling generic to display backend error messages properly
- Remove hardcoded string matching in favor of HTTP status code checks

Fixes login flow returning raw localization keys instead of user-facing messages

Fixes #2768

server/src/service/business/userService.js

@@ -83,24 +83,30 @@ class UserService {
 
 	loginUser = async (email, password) => {
 		// Check if user exists
-		const user = await this.db.userModule.getUserByEmail(email);
-		// Compare password
-		const match = await user.comparePassword(password);
-		if (match !== true) {
+		try {
+			const user = await this.db.userModule.getUserByEmail(email);
+			// Compare password
+			const match = await user.comparePassword(password);
+			if (match !== true) {
+				throw this.errorService.createAuthenticationError(this.stringService.authIncorrectPassword);
+			}
+			
+			// Remove password from user object.  Should this be abstracted to DB layer?
+			const userWithoutPassword = { ...user._doc };
+			delete userWithoutPassword.password;
+			delete userWithoutPassword.avatarImage;
+
+			// Happy path, return token
+			const appSettings = await this.settingsService.getSettings();
+			const token = this.issueToken(userWithoutPassword, appSettings);
+			// reset avatar image
+			userWithoutPassword.avatarImage = user.avatarImage;
+			return { user: userWithoutPassword, token };
+		} catch (error) {
+			// If user is not found, throw a generic authentication error for security
+			// Don't reveal whether user exists or password is wrong
 			throw this.errorService.createAuthenticationError(this.stringService.authIncorrectPassword);
 		}
-
-		// Remove password from user object.  Should this be abstracted to DB layer?
-		const userWithoutPassword = { ...user._doc };
-		delete userWithoutPassword.password;
-		delete userWithoutPassword.avatarImage;
-
-		// Happy path, return token
-		const appSettings = await this.settingsService.getSettings();
-		const token = this.issueToken(userWithoutPassword, appSettings);
-		// reset avatar image
-		userWithoutPassword.avatarImage = user.avatarImage;
-		return { user: userWithoutPassword, token };
 	};
 
 	editUser = async (updates, file, currentUser) => {

server/src/service/system/translationService.js

@@ -7,7 +7,7 @@ class TranslationService {
 		this.logger = logger;
 		this.translations = {};
 		this._language = "en";
-		this.localesDir = path.join(process.cwd(), "locales");
+		this.localesDir = path.join(process.cwd(), "src", "locales");
 	}
 
 	get serviceName() {