* fix(macos): show sessions after controls in tray menu
When many sessions are active, the injected session rows push the
toggles, action buttons, and settings items off-screen, requiring
a scroll to reach them.
Change findInsertIndex and findNodesInsertIndex to anchor just before
the separator above 'Settings…' instead of before 'Send Heartbeats'.
This ensures the controls section is always immediately visible on
menu open, with sessions appearing below.
* refactor: extract findAnchoredInsertIndex to eliminate duplication
findInsertIndex and findNodesInsertIndex shared identical logic.
Extract into a single private helper so any future anchor change
(e.g. Settings item title) only needs one edit.
* macOS: use structural tray menu anchor
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Co-authored-by: Brian Ernesto <bernesto@users.noreply.github.com>
Co-authored-by: ImLukeF <92253590+ImLukeF@users.noreply.github.com>
