- Add AdminBadge component with tooltip for content panel headers
- Use plain ShieldIcon (no tooltip) in sidebar nav items
- Render SectionHeader externally for Providers/Models with AdminBadge
- Add AdminBadge to Behavior section header

…ontent panel

- Wrap ShieldIcon in a <span> so TooltipTrigger asChild has a proper
  DOM element that can receive pointer/focus events.
- Add [scrollbar-width:thin] and matching scrollbar-color to the
  content panel's overflow container.

- Remove separate "Behavior" sidebar tab; merge system prompt into
  the "Prompts" tab below the user custom prompt, separated by an hr.
- System prompt section only renders when canSetSystemPrompt is true,
  with AdminBadge inline next to the heading.
- Set delayDuration={0} on all TooltipProvider instances so shield
  tooltips appear instantly on hover.
- Cap textareas at max-h-[240px] with thin scrollbar and minRows={4}
  so both prompts fit comfortably without the panel overflowing.
- Update stories to reflect merged tab structure.

…on headers

Add badge prop to SectionHeader that renders next to the h2 label.
Switch Providers and Models headers from action to badge so the
Admin pill sits right of the title.

…no resize

- Rename "Personal Prompt" → "Personal Instructions"
- Rename "System Prompt" → "System Instructions"
- Both textareas start at minRows={1} and auto-grow
- Placeholder: "Additional behavior, style, and tone preferences"
- Remove resize handle (resize-none)

…s when unused

…update system placeholder

- Let react-textarea-autosize manage overflow internally so scrollbar
  hides when content does not exceed max-h-[240px].
- System instructions placeholder now reads "Additional behavior,
  style, and tone preferences for all users".

The react-textarea-autosize component sets overflow:hidden as an
inline style during height measurement. Without overflow-y-auto to
override it, content disappears when adding newlines before the
height recalculates.

Removed scrollbar-color (the explicit track/thumb colors were
making the scrollbar always visually render). Kept scrollbar-width:
thin so the scrollbar is unobtrusive when it does appear at
max-height.

…descriptions

- Add mocks for getUserChatCustomPrompt and updateUserChatCustomPrompt
- Update placeholder text to match new System Instructions textarea
- Handle multiple Save buttons (personal + system forms)