feat: add user preferences dashboard

- Add /preferences route and preferences.html template for user settings
- Implement username, email, password, and theme update functionality
- Add account deletion feature with confirmation
- Add navigation link to preferences from dashboard
- Create API endpoints:
  - PUT /api/user/username - Update username
  - PUT /api/user/email - Update email address
  - PUT /api/user/password - Change password with verification
  - DELETE /api/user/account - Delete user account
- Add database queries for user updates and account deletion
- Create Bruno API testing files for all user preference endpoints
- Add proper validation, error handling, and security checks

internal/database/querier.go

@@ -18,6 +18,7 @@ type Querier interface {
 	DeleteEbook(ctx context.Context, id pgtype.UUID) error
 	DeleteEbookRating(ctx context.Context, arg DeleteEbookRatingParams) error
 	DeleteReadingProgress(ctx context.Context, arg DeleteReadingProgressParams) error
+	DeleteUser(ctx context.Context, id pgtype.UUID) error
 	DeleteUserEbookFolder(ctx context.Context, arg DeleteUserEbookFolderParams) error
 	GetEbook(ctx context.Context, id pgtype.UUID) (Ebooks, error)
 	GetEbookByFilePath(ctx context.Context, filePath string) (Ebooks, error)
@@ -29,12 +30,16 @@ type Querier interface {
 	GetUserByEmailOrUsername(ctx context.Context, email string) (Users, error)
 	GetUserByUsername(ctx context.Context, username string) (Users, error)
 	GetUserEbookFolders(ctx context.Context, userID pgtype.UUID) ([]UserEbookFolders, error)
+	GetUserPasswordHash(ctx context.Context, id pgtype.UUID) (string, error)
 	ListEbooks(ctx context.Context, arg ListEbooksParams) ([]Ebooks, error)
 	ListUsers(ctx context.Context) ([]ListUsersRow, error)
 	UpdateEbook(ctx context.Context, arg UpdateEbookParams) (Ebooks, error)
 	UpdateEbookRating(ctx context.Context, arg UpdateEbookRatingParams) (EbookRatings, error)
+	UpdateEmail(ctx context.Context, arg UpdateEmailParams) error
+	UpdatePassword(ctx context.Context, arg UpdatePasswordParams) error
 	UpdateReadingProgress(ctx context.Context, arg UpdateReadingProgressParams) (ReadingProgress, error)
 	UpdateUserTheme(ctx context.Context, arg UpdateUserThemeParams) error
+	UpdateUsername(ctx context.Context, arg UpdateUsernameParams) error
 }
 
 var _ Querier = (*Queries)(nil)