The top-bar AI button previously dispatched netcatty:toggle-ai-panel,
which was wired to handleOpenAI -> handleSwitchSidePanelTab('ai'). That
switch is a no-op when AI is already the open sub-panel, so the panel
could not be dismissed by clicking the button again.
Add a dedicated handleToggleAiFromTopBar that routes through a new
resolveAiSidePanelToggleIntent helper: a second click on an already-open
AI panel closes the side panel, while a click from a closed panel or a
different sub-panel switches to AI. The top-bar event listener now uses
this toggle handler. handleOpenAI stays a plain switch so the AI icon in
the side-panel rail remains idempotent like the other rail tabs.
Also remove the non-functional reminder (bell) button from the top bar;
it had no click handler and no backing feature.
Refs #1194
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
bincxz