Consolidate tabs, Quick Access links, mini player nav, link descriptions

- Merge Scripts/Callbacks/Links tabs into single Settings tab with collapsible sections
- Rename Actions tab to Quick Access showing both scripts and configured links
- Add prev/next buttons to mini (secondary) player
- Add optional description field to links (backend + frontend)
- Add CSS chevron indicators on collapsible settings sections
- Persist section collapse/expand state in localStorage
- Fix race condition in Quick Access rendering with generation counter
- Order settings sections: Scripts, Links, Callbacks

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

media_server/config.py

@@ -45,6 +45,7 @@ class LinkConfig(BaseModel):
     url: str = Field(..., description="URL to open")
     icon: str = Field(default="mdi:link", description="MDI icon name (e.g., 'mdi:led-strip-variant')")
     label: str = Field(default="", description="Tooltip text")
+    description: str = Field(default="", description="Optional description")
 
 
 class Settings(BaseSettings):