Open checks in the middle panel

[tyxla]

Summary

Addresses the remaining bullets from #184 — selecting a check should open it in the middle panel like any other resource.

• Clicking a check row in the project view opens it in the middle panel via the same routing drafts use (App.handlePreviewFile → handleOpenDraftEditor).
• The per-row checkbox and the edit icon are both gone from the project view — the row click is the edit affordance, so the icon would just duplicate it. Delete (trash) stays.
• While a check is open in the middle, the right sidebar mirrors the project view: only chat + checks tabs (no outline / share), the checks panel drops the Run button, and rows render without the enable/disable checkbox and without the edit icon. Clicking another check in the sidebar swaps the middle window (no inline sidebar editor).
• The draft-editor sidebar (when editing a draft / done) is unchanged — it still has outline + share + the Run button + per-row checkbox + edit icon.
• Removed the now-dead inline-editor wiring (renderCheckEditor, editingCheckRelPath, editingRelPath / renderEditor) from DraftEditorScreen, DraftSidebar, DraftChecksPanel, and useProjectChecks.

Closes #184.

Test plan

• Run npm run test:e2e -- tests/e2e/project-checks.spec.ts — covers row-click open from project view, row-click swap from the right sidebar while a check is open in the middle, sidebar shape (no outline / share, no Run, no checkbox, no edit icon), and create / delete from project view.
• Manual: open Checks tab in project view — rows show only title + delete (no checkbox, no edit icon). Click a row — opens in middle.
• Manual: while a check is open, switch to the Checks tab in the right sidebar — only chat + checks tabs are visible, no Run button, rows have no checkbox or edit icon. Click another check — middle swaps to it.
• Manual: regression — opening a draft (folder=drafts) still shows the full sidebar (chat + outline + checks + share) with the Run button, per-row checkbox, and edit icon in the checks panel.

🤖 Generated with Claude Code

[oandregal]

Thanks @tyxla

The only bit missing would be deletion: both bundled checks + user-provided checks.

The "delete" icon next to the check is not working as expected (it should work the same as removing the file from the three-dot menu at the top-right):

Screen.Recording.2026-05-20.at.16.30.17.mov

After removing a check, the checks panel should remain open.

[tyxla]

The only bit missing would be deletion: both bundled checks + user-provided checks.

The "delete" icon next to the check is not working as expected (it should work the same as removing the file from the three-dot menu at the top-right):

After removing a check, the checks panel should remain open.

#206 should address this