Preferences: Remove markdown preview preference after feature removal

- Remove markdown_preview_default field from UserPreferences model
- Remove markdown_preview_default column from user_preferences table schema
- Simplify preferences form to only show draft auto-save checkbox
- Update handler to only process auto_save_drafts preference
- Clean up unused form fields and validation logic

Only the draft auto-save preference remains.

handlers/preferences.go

@@ -21,12 +21,6 @@ func PreferencesHandler(app *App) http.HandlerFunc {
 		if r.Method == http.MethodPost {
 			// Get form values
 			autoSaveDrafts := r.FormValue("auto_save_drafts") == "on"
-			markdownPreviewDefault := r.FormValue("markdown_preview_default")
-
-			// Validate markdown_preview_default
-			if markdownPreviewDefault != "edit" && markdownPreviewDefault != "preview" {
-				markdownPreviewDefault = "edit"
-			}
 
 			// Get current preferences (or create if not exists)
 			prefs, err := models.GetUserPreferences(app.DB, userID)
@@ -38,7 +32,6 @@ func PreferencesHandler(app *App) http.HandlerFunc {
 
 			// Update preferences
 			prefs.AutoSaveDrafts = autoSaveDrafts
-			prefs.MarkdownPreviewDefault = markdownPreviewDefault
 
 			err = models.UpdateUserPreferences(app.DB, prefs)
 			if err != nil {

main.go

@@ -223,7 +223,6 @@ func createTablesIfNotExist(db *sql.DB) error {
             id INT AUTO_INCREMENT PRIMARY KEY,
             user_id INT NOT NULL UNIQUE,
             auto_save_drafts BOOLEAN DEFAULT TRUE,
-            markdown_preview_default VARCHAR(20) DEFAULT 'edit',
             created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
             updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
             FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE

models/user_preferences.go

@@ -8,12 +8,11 @@ type UserPreferences struct {
 	ID             int
 	UserID         int
 	AutoSaveDrafts bool
-	MarkdownPreviewDefault string // "edit" or "preview"
 }
 
 // GetUserPreferences retrieves preferences for a user, creating defaults if none exist
 func GetUserPreferences(db *sql.DB, userID int) (*UserPreferences, error) {
-	query := `SELECT id, user_id, auto_save_drafts, markdown_preview_default 
+	query := `SELECT id, user_id, auto_save_drafts 
 	          FROM user_preferences WHERE user_id = ?`
 
 	prefs := &UserPreferences{}
@@ -21,7 +20,6 @@ func GetUserPreferences(db *sql.DB, userID int) (*UserPreferences, error) {
 		&prefs.ID,
 		&prefs.UserID,
 		&prefs.AutoSaveDrafts,
-		&prefs.MarkdownPreviewDefault,
 	)
 
 	if err == sql.ErrNoRows {
@@ -38,8 +36,8 @@ func GetUserPreferences(db *sql.DB, userID int) (*UserPreferences, error) {
 
 // CreateDefaultPreferences creates default preferences for a new user
 func CreateDefaultPreferences(db *sql.DB, userID int) (*UserPreferences, error) {
-	query := `INSERT INTO user_preferences (user_id, auto_save_drafts, markdown_preview_default) 
-	          VALUES (?, TRUE, 'edit')`
+	query := `INSERT INTO user_preferences (user_id, auto_save_drafts) 
+	          VALUES (?, TRUE)`
 
 	result, err := db.Exec(query, userID)
 	if err != nil {
@@ -55,16 +53,15 @@ func CreateDefaultPreferences(db *sql.DB, userID int) (*UserPreferences, error)
 		ID:             int(id),
 		UserID:         userID,
 		AutoSaveDrafts: true,
-		MarkdownPreviewDefault: "edit",
 	}, nil
 }
 
 // UpdateUserPreferences updates user preferences
 func UpdateUserPreferences(db *sql.DB, prefs *UserPreferences) error {
 	query := `UPDATE user_preferences 
-	          SET auto_save_drafts = ?, markdown_preview_default = ?, updated_at = NOW() 
+	          SET auto_save_drafts = ?, updated_at = NOW() 
 	          WHERE user_id = ?`
 
-	_, err := db.Exec(query, prefs.AutoSaveDrafts, prefs.MarkdownPreviewDefault, prefs.UserID)
+	_, err := db.Exec(query, prefs.AutoSaveDrafts, prefs.UserID)
 	return err
 }

templates/pages/preferences.html

@@ -28,19 +28,6 @@
                     Drafts are saved to your browser's local storage and restored when you return to chat.
                 </p>
 
-                <h3 style="margin-top: 2em;">Markdown Preview</h3>
-                <label for="markdown_preview_edit" style="display: flex; align-items: center; gap: 0.5em; cursor: pointer; margin-bottom: 0.5em;">
-                    <input type="radio" id="markdown_preview_edit" name="markdown_preview_default" value="edit" {{if eq .Preferences.MarkdownPreviewDefault "edit"}}checked{{end}}>
-                    <span>Default to <strong>Edit</strong> mode (write markdown)</span>
-                </label>
-                <label for="markdown_preview_preview" style="display: flex; align-items: center; gap: 0.5em; cursor: pointer;">
-                    <input type="radio" id="markdown_preview_preview" name="markdown_preview_default" value="preview" {{if eq .Preferences.MarkdownPreviewDefault "preview"}}checked{{end}}>
-                    <span>Default to <strong>Preview</strong> mode (see formatted output)</span>
-                </label>
-                <p style="margin-left: 1.5em; margin-top: 0.25em; font-size: 0.9em; opacity: 0.8;">
-                    Choose which tab is shown by default when composing messages in chat.
-                </p>
-
                 <input type="submit" value="Save Preferences" style="margin-top: 2em;">
             </form>
         </section>