Merge website-branding feature and adjust for compatibility

- Resolved conflicts in models.py, app.py, and template files
- Added branding checks to prevent errors when g.branding is None
- Updated all template references to use conditional branding
- Added BrandingSettings to migrations
- Created branding uploads directory
- Integrated branding with existing comment and task management features

models.py

@@ -195,16 +195,18 @@ class User(db.Model):
         import pyotp
         self.two_factor_secret = pyotp.random_base32()
         return self.two_factor_secret
-
-    def get_2fa_uri(self):
+    
+    def get_2fa_uri(self, issuer_name=None):
         """Get the provisioning URI for QR code generation"""
         if not self.two_factor_secret:
             return None
         import pyotp
         totp = pyotp.TOTP(self.two_factor_secret)
+        if issuer_name is None:
+            issuer_name = "Time Tracker"  # Default fallback
         return totp.provisioning_uri(
             name=self.email,
-            issuer_name="TimeTrack"
+            issuer_name=issuer_name
         )
 
     def verify_2fa_token(self, token, allow_setup=False):
@@ -267,6 +269,38 @@ class SystemSettings(db.Model):
     def __repr__(self):
         return f'<SystemSettings {self.key}={self.value}>'
 
+class BrandingSettings(db.Model):
+    id = db.Column(db.Integer, primary_key=True)
+    app_name = db.Column(db.String(100), nullable=False, default='Time Tracker')
+    logo_filename = db.Column(db.String(255), nullable=True)  # Filename of uploaded logo
+    logo_alt_text = db.Column(db.String(255), nullable=True, default='Logo')
+    favicon_filename = db.Column(db.String(255), nullable=True)  # Filename of uploaded favicon
+    primary_color = db.Column(db.String(7), nullable=True, default='#007bff')  # Hex color
+    
+    # Meta fields
+    created_at = db.Column(db.DateTime, default=datetime.now)
+    updated_at = db.Column(db.DateTime, default=datetime.now, onupdate=datetime.now)
+    updated_by_id = db.Column(db.Integer, db.ForeignKey('user.id'), nullable=True)
+    
+    # Relationships
+    updated_by = db.relationship('User', foreign_keys=[updated_by_id])
+    
+    def __repr__(self):
+        return f'<BrandingSettings {self.app_name}>'
+    
+    @staticmethod
+    def get_current():
+        """Get current branding settings or create defaults"""
+        settings = BrandingSettings.query.first()
+        if not settings:
+            settings = BrandingSettings(
+                app_name='Time Tracker',
+                logo_alt_text='Application Logo'
+            )
+            db.session.add(settings)
+            db.session.commit()
+        return settings
+
 class TimeEntry(db.Model):
     id = db.Column(db.Integer, primary_key=True)
     arrival_time = db.Column(db.DateTime, nullable=False)