[codex] Add remaining 2.1.0 issue fixes

[teddychan]

Summary

• Implemented README-listed menu bar organization features: layout profiles, item groups, spacers, trigger conditions, extra hotkey actions, and the option to remove the overlay background behind the menu bar.
• Fixed remaining upstream behavior issues around click/scroll reveal, external displays, active menu bar detection, Tahoe layout handling, search visibility, and appearance persistence.
• Updated CHANGELOG.md with clear fix notes and original upstream references including [Bug]: Option-Click does not work if Show on Click is disabled jordanbaird/Ice#634, [Bug]: Clickable area to activate Ice extends beyond menu bar to blank area of 2nd monitor. jordanbaird/Ice#646, [Bug]: Show on swipe works but not scroll jordanbaird/Ice#717, [Bug]: Menu Bar Layout settings is empty jordanbaird/Ice#744, [Bug]: The cursor is not visible after clicking the ICE icon and then selecting a hidden icon from the ICE bar. jordanbaird/Ice#751, [Bug]: Ice Icon Disappearing after Hidden Items are shown jordanbaird/Ice#759, [Bug]: Right-clicking in external monitor opens "Edit menu bar appearance" menu jordanbaird/Ice#824, Add Simplified Chinese localization and fix fullscreen menu bar trigger on notchless displays jordanbaird/Ice#868, [Bug]: ICons List Blank In Settings jordanbaird/Ice#891, [Bug]: Ice triggering while clicking just under the menu bar in fullscreen jordanbaird/Ice#899, Fix IceBar click flakiness on macOS 26 (notched + Control Center reparenting) jordanbaird/Ice#911, Fix "Unable to display menu bar items" on macOS 26.4 jordanbaird/Ice#922, [Bug]: Crash when enabling "Use Ice Bar" with Dynamic location jordanbaird/Ice#925, fix(xpc): make MenuBarItemService work for ad-hoc-signed builds on macOS 26 jordanbaird/Ice#950, Allow MenuBarItemService XPC connection on builds without a Team Identifier jordanbaird/Ice#953, and PR [Bug]: Option-click should expand even when enable always-hidden section is turned off jordanbaird/Ice#595.

Validation

• git diff --check
• git diff --cached --check
• Build intentionally not run per request.

Release

• Tagged this commit as 2.1.0 and pushed the tag to origin.

[teddychan]

Reviewed this PR (high-effort, multi-angle). Not merging as-is — verification found one confirmed functional bug plus several plausible regressions:

• Confirmed: Ice's own spacer items get captured into layout profiles / item groups and then moved/clicked on profile-apply or trigger (only isControlItem was excluded, not isSpacerItem).
• Plausible: overlay panel frame built from CoreGraphics window bounds (Y-down) passed to NSPanel.setFrame (AppKit, Y-up) with no conversion → mis-positioned on non-primary displays; temporarily-shown items matched only by windowID (unstable across window recreation) → can be stranded; duplicate default profile/group names after deletions.

Rather than merge here, I opened #2 which contains this branch's work plus the corrections (and a couple of quality cleanups). See that PR for the full list, including items I reviewed and intentionally left unchanged. Suggest closing this in favor of #2 once #2 builds green in CI.

Note: build was not run in either case — please CI-build #2 before release.

[teddychan]

Note: GitHub auto-marked this as merged because #2 (built on top of this branch) landed on main — #2 contains all of this branch's commits plus the review-fix corrections. The corrected work is what shipped; no action needed here.