feat(office): add Workspace TUI with shared bootstrap and test suite

Introduce the office Bubble Tea browser (module tree, multi-select lists,
markdown preview) alongside oo, with cmd/internal/bootstrap for shared auth,
unit tests across preview/model/ui/fetch, CI build for both binaries, and
GoReleaser archives for office.

Co-authored-by: Cursor <cursoragent@cursor.com>

.github/workflows/test.yml

@@ -42,5 +42,8 @@ jobs:
       - name: Build oo
         run: go build -trimpath -buildvcs=false -o /tmp/oo ./cmd/oo
 
+      - name: Build office
+        run: go build -trimpath -buildvcs=false -o /tmp/office ./cmd/office
+
       - name: Run tests
         run: go test -race -shuffle=on -count=1 ./...