* refactor(chat): adjust mobile controls layout
Improve alignment of mobile model and agent buttons with action buttons
Constrain mobile controls to a max width to prevent overflow on small screens
* fix: improve MobileAgentButton mobile interaction
Replace touch-none with touch-pan-x to enable horizontal swipe
Wrap the agent label in a scrollable container to prevent truncation
* fix(ui): allow horizontal scroll for model label
Enable horizontal scrolling for long model labels on mobile
Prevent truncation by letting the label overflow horizontally
Improve visibility by keeping the full label accessible without clipping
* feat(mobile): split controls into separate Agent and Model buttons
- Add MobileAgentButton with tap-to-cycle and long-press-to-open behavior
- Add MobileModelButton for direct model panel access
- Remove agent selection from UnifiedControlsDrawer for cleaner mobile UX
- Agent cycling accessible via Tab key shortcut
* fix(mobile): optimize controls layout and touch handling
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Co-authored-by: Jovines <jovines@qq.com>