Backend changes:
- Add civitai_api_key to _NO_SYNC_KEYS, return only boolean civitai_api_key_set
- Clean up known template placeholder on load to prevent false positive
Frontend changes:
- Replace type=password with type=text + CSS masking (-webkit-text-security)
- Replace pre-filled input with status display (Configured/Not configured)
- Add inline edit view with Save/Cancel buttons
- Re-add eye toggle via CSS class toggle (not type switching)
- Use CSS transitions for smooth status/edit view switching
This prevents Chromium/Vivaldi password manager from triggering
'save password' prompts when opening the settings modal.
Replace _SYNC_KEYS (37 keys) with _NO_SYNC_KEYS (5 keys) in SettingsHandler.
New settings automatically sync to frontend unless explicitly excluded.
Changes:
- SettingsHandler now syncs all settings except those in _NO_SYNC_KEYS
- Added keys() method to SettingsManager for iteration
- Updated tests to use new behavior
Benefits:
- No more missing keys when adding new settings
- Reduced maintenance burden
- Explicit exclusions for sensitive/internal settings only
Fixes: #86
