feat(sidebar): group bulk actions, empty-area quick menu, sort

[mortenaslo]

Summary

• Per-group bulk actions — right-click a group (strip tab or inline header) now offers Remote control all, Sleep all, Wake all, Close all… The items disable based on live vs. dormant counts.
• Empty-area quick menu — right-click on empty sidebar header, session list, group strip, or terminal grid surfaces a shared menu with New session, New group…, Bulk actions submenu (Wake all dormant / Sleep all / Close all), Group display mode, Expand/Collapse all groups, Session row icons mode, Show git branch / worktree clusters toggles, and All settings…. The legacy footer "+" group button is gone; group creation flows through this menu.
• Sort sessions button — new ⇅ button in the SESSIONS header (left of +). Direction-aware sort menu with Name / Folder / Last active / Git ▸ (Branch, Dirty, Repo). Re-clicking the active field flips direction; switching fields picks each field's natural starting direction. Direction glyph lives in the MenuItem icon slot so it column-aligns; the active row renders SemiBold + 100% opacity, inactive rows show their default direction as a 45%-opacity preview.
• Visual polish — vertical filter strip hairline divider between All/Ungrouped and user groups; Ungrouped glyph "∅" → "□" so it reads as the hollow companion to "▦".

Implementation notes

• ShellSession.LastActivityAt (defaults to CreatedAt) is updated whenever the active session changes, persisted via the existing state.json flow.
• SessionManager.SortSessions(Comparison<ShellSession>) is a one-shot in-place sort; drag-reorder still works afterwards.
• Git-based sorts build a one-time Dictionary<id, SessionViewModel> lookup; dormant sessions (no live VM) sink to the bottom of every git ordering.

Test plan

• Right-click a group in both the filter strip and an inline header: verify bulk actions enable/disable per group population and that confirm dialog fires on Close all.
• Right-click empty sidebar / terminal grid: verify menu opens with all entries, and item-level menus on session rows / group tabs still shadow it.
• Toggle Group display modes: None / FilterStrip / InlineHeaders all rebuild cleanly.
• InlineHeaders mode + multiple groups: Expand all / Collapse all flips every section and persists across restart.
• Sort by each field: arrow flips on re-click, switches to natural default on new field; verify Git fields keep dormant rows at the bottom and worktrees adjacent within the same branch/repo.
• Restart with sessions active in different states: LastActivityAt updates make "Last active" reflect recent navigation.

🤖 Generated with Claude Code

[AThraen]

Code review

Found 1 issue:

1. LastActivityAt property initializer is DateTime.UtcNow, but its own XML doc promises it defaults to CreatedAt for sessions that predate the field. System.Text.Json fires the property initializer at deserialization time when the JSON key is missing, so every legacy session loaded from a pre-PR state.json gets LastActivityAt = <load time> — not its CreatedAt. "Sort by Last active" then ranks all legacy sessions as if they were just touched (in load order) until each is activated once. Fix is either a sentinel + getter coalesce, or a one-time backfill from CreatedAt during state load.

CodeShellManager/src/CodeShellManager/Models/ShellSession.cs

Lines 19 to 28 in dd4ebd4

	public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
	/// <summary>
	/// Last time the user gave this session focus (clicked it in the sidebar, woke it,
	/// or it was selected via Ctrl+Tab). Persisted so "Sort by last active" survives
	/// restarts. Defaults to <see cref="CreatedAt"/> for sessions that have never been
	/// activated since the field was introduced.
	/// </summary>
	public DateTime LastActivityAt { get; set; } = DateTime.UtcNow;

🤖 Generated with Claude Code

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