fix(workspaces): clear sync row on close so overview doesn't tag closed workspaces as "other device"

[Zeus-Deus]

Summary

• After closing a workspace, the Workspaces overview briefly rendered the just-closed workspace as "lives on another device" until the 30 s background reconcile loop caught up.
• Root cause: both close paths in commands/workspace.rs removed the workspace from app_state and emitted to the frontend, but never reconciled workspaces_sync. The orphan sync row (now with a workspace_id that no longer matched any live workspace) was then classified as kind: "remote" by useOverviewItems and rendered with the "other device" badge.
• Fix:
  1. Backend (root cause) — close_workspace_with_worktree_impl and close_workspace now reconcile_from_snapshot immediately after state.close_workspace(...) so the orphan row is soft-deleted in the same tick the frontend re-renders, then best-effort try_sync_with_app so sibling devices learn about the close without waiting for the 30 s tick. Failures are non-fatal (logged) — the close itself already succeeded.
  2. Frontend (defense in depth) — useOverviewItems step 2 now skips sync rows whose workspace_id is non-null. True sibling-device rows always have workspace_id === null until adoption, so a non-null workspace_id with no matching local workspace can only be a self-orphan, never an actual sibling-device row.

Test plan

• cargo check --manifest-path src-tauri/Cargo.toml
• cargo test --manifest-path src-tauri/Cargo.toml --lib workspaces_sync::tests:: — 9/9 pass, including 3 new ones:
  • reconcile_inserts_row_for_new_workspace
  • reconcile_soft_deletes_row_when_workspace_closed (regression guard)
  • reconcile_preserves_pulled_only_rows
• npm run check (tsc) — clean
• npm run test — 1766 tests pass, including 5 new ones in use-overview-items.test.ts covering kind:local / kind:remote classification and the self-orphan skip
• Manual reproduction: closing a workspace no longer shows it as "other device" in the overview

Pre-existing failing test on origin/main not introduced by this PR: commands::mcp::tests::project_codemux_entry_is_filtered_out (reproduces on a clean checkout of main).

Incidental

package-lock.json picks up the 0.6.1 → 0.7.0 version follow-on from commit 20f539a chore: bump version to 0.7.0.