fix(ci): switch npm publish to OIDC trusted publishing

NODE_AUTH_TOKEN expired (set 90 days ago, the npm token default
expiry) causing all publish runs to fail with 'PUT 404 Not Found'
since 2026-04-30.

Migrate publish.yml and publish-platform.yml to npm Trusted
Publishing (OIDC) so we no longer depend on long-lived secrets:

- Bump actions/setup-node v4 -> v6 (improves OIDC compatibility)
- Add 'npm install -g npm@latest' to guarantee npm CLI >= 11.5.1
  (the minimum required for trusted publishing).
- Drop NODE_AUTH_TOKEN env from every publish step. The npm CLI
  picks up the GitHub Actions OIDC token automatically.
- Keep --provenance / NPM_CONFIG_PROVENANCE=true (real-world
  reports indicate provenance is not auto-emitted yet).

Per-package trusted publisher must still be configured on
npmjs.com (Settings -> Trusted Publisher) for all 24 packages
(oh-my-opencode + oh-my-openagent main + 11 platform packages
each, dual-published) before the next publish run.

.github/workflows/publish-platform.yml

@@ -342,17 +342,20 @@ jobs:
           ls -la packages/${PLATFORM}/
           ls -la packages/${PLATFORM}/bin/
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         if: steps.check.outputs.skip_all != 'true' && steps.download.outcome == 'success'
         with:
           node-version: "24"
           registry-url: "https://registry.npmjs.org"
 
+      - name: Upgrade npm for trusted publishing (>=11.5.1)
+        if: steps.check.outputs.skip_all != 'true' && steps.download.outcome == 'success'
+        run: npm install -g npm@latest
+
       - name: Publish oh-my-opencode-${{ matrix.platform }}
         if: steps.check.outputs.skip_opencode != 'true' && steps.download.outcome == 'success'
         env:
           DIST_TAG: ${{ steps.validate.outputs.dist_tag }}
-          NODE_AUTH_TOKEN: ${{ secrets.NODE_AUTH_TOKEN }}
           NPM_CONFIG_PROVENANCE: true
         run: |
           cd packages/${{ matrix.platform }}
@@ -368,7 +371,6 @@ jobs:
         if: steps.check.outputs.skip_openagent != 'true' && steps.download.outcome == 'success'
         env:
           DIST_TAG: ${{ steps.validate.outputs.dist_tag }}
-          NODE_AUTH_TOKEN: ${{ secrets.NODE_AUTH_TOKEN }}
           NPM_CONFIG_PROVENANCE: true
         run: |
           cd packages/${{ matrix.platform }}

.github/workflows/publish.yml

@@ -83,11 +83,14 @@ jobs:
         with:
           bun-version: "1.3.11"
 
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@v6
         with:
           node-version: "24"
           registry-url: "https://registry.npmjs.org"
 
+      - name: Upgrade npm for trusted publishing (>=11.5.1)
+        run: npm install -g npm@latest
+
       - name: Install dependencies
         run: bun install
         env:
@@ -170,7 +173,6 @@ jobs:
         if: steps.check.outputs.skip != 'true'
         env:
           DIST_TAG: ${{ steps.version.outputs.dist_tag }}
-          NODE_AUTH_TOKEN: ${{ secrets.NODE_AUTH_TOKEN }}
           NPM_CONFIG_PROVENANCE: true
         run: |
           if [ -n "$DIST_TAG" ]; then
@@ -197,7 +199,6 @@ jobs:
         env:
           VERSION: ${{ steps.version.outputs.version }}
           DIST_TAG: ${{ steps.version.outputs.dist_tag }}
-          NODE_AUTH_TOKEN: ${{ secrets.NODE_AUTH_TOKEN }}
           NPM_CONFIG_PROVENANCE: true
         run: |
           # Update package name, version, and optionalDependencies for oh-my-openagent