05. Rebuild Shell chrome — drop sidebar, add yazi bottom status/tab bar

meta: id: yazi-remake-05 feature: yazi-remake priority: P1 depends_on: [yazi-remake-01] tags: [implementation, shell-chrome, tests-required]

objective:

Remove the always-on left tab sidebar entirely and replace it with a full-width page area above a slim yazi-style bottom bar that surfaces the active tab, depth/counts, selection, now-playing, and a discoverable tab strip.

deliverables:

src/components/Shell.tsx — sidebar JSX deleted; render LayerGraph[tab]() full-width + a rebuilt bottom status/command bar
Bottom bar (normal mode): mode label, TAB_LABEL[tab] · depth N · i/len (or pane i/n for fixed tabs), selection count ●N, now-playing ♪ title, pending-keybind hint, and a compact tab strip [1]Feed [2]MyShows … with the active tab marked
Bottom bar (command mode): : prompt + buffer + error (unchanged, just relocated if needed)
Help overlay kept; now-playing relocated from the old sidebar footer into the status bar

steps:

Read Shell.tsx and delete the entire left tab sidebar <box flexDirection="column" width={14}>… block
Replace the middle row with a single full-width <box flexGrow={1}>{LayerGraph[nav.activeTab()]()}</box>
Rebuild the bottom bar: a height-1 <box flexDirection="row"> with the fragments described above
Tab strip: render Object.values(TABS) filtered to numbers; for each tab show [N] Label with the active tab inverted/highlighted (accent bg or ≡ marker)
Status fragment: nav.activePane() === DEPTH_CENTER_PANE ? (isDepthTab ? \depth ${currentDepth()}` : `pane ${activePane()+1}/${count}`) : 'tabs'` — but since the sidebar is gone, default to the depth/pane string (focus starts on current)
Relocate nowPlaying() text from the sidebar footer into the bottom bar
Keep runCommand, handleCommandKey, the help overlay, and playEpisodeAndSwitch untouched
Run diagnostics

tests:

Unit: nowPlaying() formats ♪ <truncated title> (Arrange a current episode, Assert the string)
Integration: switching tabs updates the tab strip's active marker and the status tab label
e2e (harness): init shows no left sidebar, a full-width page, and a bottom bar containing the tab strip + Feed · depth 0; cycling tabs moves the strip's active marker

acceptance_criteria:

No width={14} sidebar <box> remains in Shell.tsx
The active page fills the full content width
The bottom bar shows the active tab, depth, counts, selection, now-playing, and the tab strip
The active tab is visually marked in the strip

validation:

grep -n "width={14}" src/components/Shell.tsx returns nothing
grep -n "LayerGraph" src/components/Shell.tsx shows the full-width render
lens_diagnostics paths=[src/components/Shell.tsx] severity=error → 0 findings
Harness: init frame has no sidebar column and shows the tab strip in the last row

notes:

Depends on 01 (the pane model: focus starts on current, so the status fragment no longer needs the SIDEBAR_PANE branch)
Task 06 rewrites the dispatch keybinds in this same file; do the chrome here and leave the dispatch SIDEBAR_ACTIONS branch for 06 to remove (or remove it here if 01 already deleted the constant — coordinate with 01)
playEpisodeAndSwitch and the command bar must keep working