feat: add Changesets for automated npm releases

Add @changesets/cli with config linking manifest and @manifest/server
packages. Mark backend and frontend as private to exclude from
publishing. Add release workflow (changesets/action) for automated npm
publishing on push to main, and changeset status check in CI for PRs.
Rename @mnfst/manifest-server to @manifest/server.

Author: brunobuddy

.changeset/README.md

@@ -0,0 +1,21 @@
+# Changesets
+
+This folder is managed by [Changesets](https://github.com/changesets/changesets).
+
+## Adding a changeset
+
+When you make a change to a publishable package (`manifest` or `@manifest/server`), run:
+
+```bash
+npx changeset
+```
+
+Follow the prompts to select the affected packages and the semver bump type (patch / minor / major). This creates a markdown file in this folder describing the change.
+
+Commit the changeset file along with your code changes.
+
+## How releases work
+
+1. PRs that include changeset files get merged into `main`.
+2. The release workflow opens a "Version Packages" PR that bumps versions and updates changelogs.
+3. When that PR is merged, the workflow publishes the new versions to npm.

.changeset/config.json

@@ -0,0 +1,11 @@
+{
+  "$schema": "https://github.com/changesets/changesets/blob/main/packages/config/schema.json",
+  "changelog": "@changesets/cli/changelog",
+  "commit": false,
+  "fixed": [],
+  "linked": [["manifest", "@manifest/server"]],
+  "access": "public",
+  "baseBranch": "main",
+  "updateInternalDependencies": "patch",
+  "ignore": []
+}

.github/workflows/ci.yml

@@ -66,6 +66,8 @@ jobs:
           cache: npm
       - run: npm ci
       - run: npm run build --workspace=packages/backend
+      - name: Unit tests (SQLite dialect)
+        run: npm test --workspace=packages/backend
       - name: E2E tests (SQLite in-memory)
         run: npm run test:e2e --workspace=packages/backend
 
@@ -94,3 +96,18 @@ jobs:
           cache: npm
       - run: npm ci
       - run: npm test --workspace=packages/openclaw-plugin
+
+  changeset-check:
+    name: Changeset status
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request'
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+      - run: npm ci
+      - run: npx changeset status --since=origin/main

.github/workflows/release.yml

@@ -0,0 +1,30 @@
+name: Release
+
+on:
+  push:
+    branches: [main]
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: npm
+          registry-url: https://registry.npmjs.org
+      - run: npm ci
+      - run: npm run build
+      - uses: changesets/action@v1
+        with:
+          publish: npm run release
+          version: npm run version-packages
+          title: "chore: version packages"
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}