feat(comms): Slack + Zoom/Meet apps on the shared foundation; CI build-order fix

Wave 1 comms hubs land:
- @hanzo/slack — /hanzo slash command, App Home, message shortcuts, thread-context
  quick actions, OAuth install; UI 100% @hanzo/cards Block Kit (68 tests).
- @hanzo/meetings — Zoom App + Google Meet add-on panels + Zoom webhook
  transcript→summary (signature-verified); web panels over @hanzo/ai (70 tests).

CI: build @hanzo/cards before dependent tests (consumers resolve its built dist/),
and add slack + meetings test steps.

Note: the headless @hanzo/ai client isn't published under 'latest' yet (npm
@hanzo/ai@0.1.1 is the React <HanzoAI/> UI); each adapter ships a client to the
exact createAiClient /v1 contract as an interim, to become a one-line re-export
once the headless client publishes.

.github/workflows/ci.yml

@@ -21,6 +21,11 @@ jobs:
         cache: 'pnpm'
     - run: pnpm install --frozen-lockfile
 
+    # Build shared workspace libraries first — consumers (slack/teams/…) import
+    # @hanzo/cards via its built dist/, so it must exist before their tests run.
+    - name: Build shared libraries
+      run: pnpm --filter @hanzo/cards build
+
     - name: Test browser extension
       run: pnpm --filter @hanzo/browser-extension test
 
@@ -51,6 +56,12 @@ jobs:
     - name: Test cards (shared card-builder)
       run: pnpm --filter @hanzo/cards test
 
+    - name: Test Slack app
+      run: pnpm --filter @hanzo/slack test
+
+    - name: Test Zoom + Meet
+      run: pnpm --filter @hanzo/meetings test
+
     - name: Test tools package
       run: pnpm --filter @hanzo/cli-tools test