Activity sidebar, project selectors, and the end of tabs

[wingleeio]

Sidebar/composer restructure (t3 code-inspired), building on #14's spaces dropdown.

What changed

Sidebar is activity-first. Rows follow the t3 code card anatomy: line 1 is project @ device with a colored status word top-right (Working with live spinner / Input / Failed / Done — relative time when idle), line 2 the title, line 3 the harness mark + branch. The header dropdown filters by project (ported from #14, now labeled All projects), and the header + is New session — project creation moved into the dropdown's "New project…" row.

Horizontal tabs are gone. The titlebar names the selected session — harness icon + title, left-aligned. When the sidebar collapses, the new-session + fades into the titlebar riding the same width tween (UiSettings.open_tabs is legacy, no longer read).

Two new selectors under the composer. A device selector (defaults to the last selected device) and a project selector (defaults to the last selected project), persisted in composer-defaults.json. Checkout + ref chips only appear when a git project is selected, with checkout to the left of ref.

Sessions without a project. The project picker's "Don't work in a project" row mints sessions with no project: createChat now takes an optional spaceId + deviceId, the chat's cwd is stored as ~ and expanded on the host when the run spawns. They show as ~ @ device in the sidebar (first shot, third row).

Refs are fixed at creation. Existing sessions can no longer change refs — the mid-session switchRef path is deleted and the session footer renders read-only checkout/ref labels. Refs (and checkout kind, device, project) are chosen on the new-session canvas only.

Spaces → projects in all user-facing copy ("All projects", "New project…", "Search projects…", onboarding). Internal identifiers and the synced doc schema are untouched — Space rows, createSpace/renameSpace ops etc. keep their names, so no migration.

Engine changes

• Mutate createChat: spaceId optional, new optional deviceId (host for project-less chats); cwd defaults to ~ when no project.
• sessions::dispatch_inner expands ~/~/… against the host's home before resume-scoping and spawn.

Notes

• Builds on Device-local tabs + spaces as a searchable sidebar filter #14 (merged into this branch); that PR's device-local-tabs half is superseded by removing tabs entirely — closing it in favor of this.
• Boot lands on the most recent session (the old pre-tabs behavior); the "Don't work in a project" opt-out survives restarts and wins over last_space_id restore.
• 382 UI + all engine tests pass; screenshots from the headless demo rig, hosted as user content (not in the repo).

🤖 Generated with Claude Code

---

^{Need help on this PR? Tag @codesmith-bot with what you need. Autofix is disabled.}

[wingleeio]

Polish round (eb0657e), per wing's feedback:

• Status text restyled — medium weight, check glyph on Done; hovering a row swaps the status/time for an Archive button (t3 code's settle-on-hover):

  

• Device + project are always visible under the composer on sessions too — read-only labels beside the locked checkout/ref pair (wing-mbp · comet … Local checkout · main above). Project label is omitted when the session has no project.

• Device popover gains a search box; "Don't work in a project" wears an ×; the new-session + lost its active wash:

  

• Sidebar filter drives canvas defaults: with a project filter set, a new session defaults to that project and its device (beats last-selected and the no-project opt-out).

🤖 Generated with Claude Code

[wingleeio]

Two more fixes (45eceef):

• Titlebar + spacing — the collapsed-sidebar new-session + now renders inside the window-control cluster (same 24px slot, same 2px gap as sidebar/back/forward) instead of floating 10px off it:

  

• Archive is corner-hover only — hovering the row body keeps the status word readable; the swap happens only over the status/time itself:

  

🤖 Generated with Claude Code