feat(deploy): add frontend production deployment workflow and skill

Add a GitHub Actions workflow (workflow_dispatch) that promotes the
latest Vercel staging deployment to production using `vercel promote`.
Agents can trigger this via `gh workflow run`, enabling @-mention
driven deployments from Multica.

Also adds a deploy-frontend Claude Code skill with step-by-step
instructions for agents, and updates .gitignore to track skills.

.claude/skills/deploy-frontend/SKILL.md

@@ -0,0 +1,68 @@
+---
+name: deploy-frontend
+description: >
+  Deploy the Multica frontend to production. Use this skill when asked to deploy the frontend,
+  promote to production, or ship the web app. Triggers a GitHub Actions workflow that promotes
+  the latest Vercel staging deployment to production.
+---
+
+# Deploy Frontend to Production
+
+## Overview
+
+The Multica frontend (Next.js app in `apps/web/`) is hosted on Vercel:
+
+- **Staging** (`https://multica-app.copilothub.ai`): Auto-deploys on every merge to `main`.
+- **Production**: Promoted from staging via the `Deploy Frontend to Production` GitHub Actions workflow.
+
+## How to Deploy
+
+### 1. Verify Staging
+
+Before deploying, confirm that staging is healthy. Ask the user or check:
+
+- The latest CI on `main` is green.
+- Staging (`https://multica-app.copilothub.ai`) is working correctly.
+
+### 2. Trigger the Deployment
+
+Run the GitHub Actions workflow:
+
+```bash
+gh workflow run "Deploy Frontend to Production" --repo multica-ai/multica
+```
+
+### 3. Monitor the Deployment
+
+Watch the workflow run:
+
+```bash
+gh run list --repo multica-ai/multica --workflow="Deploy Frontend to Production" --limit 1
+```
+
+To get detailed status:
+
+```bash
+gh run watch --repo multica-ai/multica $(gh run list --repo multica-ai/multica --workflow="Deploy Frontend to Production" --limit 1 --json databaseId --jq '.[0].databaseId')
+```
+
+### 4. Report the Result
+
+After the workflow completes, post the result as a comment on the relevant issue. Include:
+
+- Whether the deployment succeeded or failed.
+- A link to the workflow run.
+
+## Required Secrets
+
+The GitHub Actions workflow requires these secrets (configured in the repo settings):
+
+- `VERCEL_TOKEN` — Vercel API token with deploy permissions
+- `VERCEL_PROJECT_ID` — The Vercel project ID for `multica-web-production`
+- `VERCEL_ORG_ID` — The Vercel organization (team) ID for `indexlabs`
+
+## Troubleshooting
+
+- **Workflow not found**: Ensure the workflow file exists at `.github/workflows/deploy-production.yml`.
+- **Permission denied**: The `gh` CLI must be authenticated with repo access.
+- **Vercel errors**: Check that the secrets are correctly configured in the repo settings.

.github/workflows/deploy-production.yml

@@ -0,0 +1,27 @@
+name: Deploy Frontend to Production
+
+on:
+  workflow_dispatch:
+    inputs:
+      skip_confirmation:
+        description: "Skip confirmation (for automated triggers)"
+        required: false
+        default: "false"
+
+concurrency:
+  group: deploy-production
+  cancel-in-progress: false
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    environment: production
+    steps:
+      - name: Install Vercel CLI
+        run: npm install -g vercel@latest
+
+      - name: Promote to Production
+        run: vercel promote --yes --token=${{ secrets.VERCEL_TOKEN }} --scope=indexlabs
+        env:
+          VERCEL_PROJECT_ID: ${{ secrets.VERCEL_PROJECT_ID }}
+          VERCEL_ORG_ID: ${{ secrets.VERCEL_ORG_ID }}

.gitignore

@@ -34,8 +34,9 @@ apps/web/test-results/
 # context (agent workspace)
 .context
 
-# local settings
-.claude/
+# local settings — ignore .claude/ except skills
+.claude/*
+!.claude/skills/
 
 # feature tracking
 _features/