ci: migrate release-please to CLI + accept LABELER_PAT fallback

.github/workflows/label-pr.yml

@@ -13,11 +13,22 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
 
+    # Prefer the maintainer-provided PAT (`LABELER_PAT`) when set, fall
+    # back to the workflow's auto-generated `GITHUB_TOKEN` otherwise.
+    # GitHub started rejecting the auto token on POST /labels with
+    # spurious 401 "Bad credentials" earlier in 2026; a fine-grained
+    # PAT scoped to this repo (issues: write + pull_requests: write)
+    # is the documented escape hatch. Empty secrets are falsy in this
+    # ternary, so unset → fallback works without extra plumbing.
+    env:
+      LABEL_TOKEN: ${{ secrets.LABELER_PAT || secrets.GITHUB_TOKEN }}
+
     steps:
       # Scope labels based on changed files
       - name: Path-based labels
         uses: actions/labeler@f27b608878404679385c85cfa523b85ccb86e213 # v6.1.0
         with:
+          repo-token: ${{ env.LABEL_TOKEN }}
           sync-labels: true
 
       # Type labels based on PR title (conventional commits)
@@ -26,6 +37,7 @@ jobs:
       - name: Type labels
         uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         with:
+          github-token: ${{ env.LABEL_TOKEN }}
           script: |
             const title = context.payload.pull_request.title;
             const prefixMap = {
@@ -56,6 +68,7 @@ jobs:
       - name: Size labels
         uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
         with:
+          github-token: ${{ env.LABEL_TOKEN }}
           script: |
             const { data: files } = await github.rest.pulls.listFiles({
               owner: context.repo.owner,

.github/workflows/release-please.yml

@@ -12,6 +12,17 @@ name: Release Please
 # (release-please-bump-lockfile.yml) that listens to the
 # release-please PR being opened / synchronized — release-please
 # can't bump Cargo.lock natively because it's regenerated by cargo.
+#
+# **Migrated 2026-05 from `googleapis/release-please-action@v5.0.0`
+# (deprecated, bundling an older release-please library) to the
+# CLI directly because the action started returning persistent
+# 401 "Bad credentials" on its GitHub API calls. The CLI uses the
+# same `GITHUB_TOKEN` cleanly. Behaviour is identical from the
+# caller's perspective: same release PR branch
+# (`release-please--branches--main--components--waveflow`), same
+# `github-actions[bot]` author, so the lockfile-build companion
+# workflow keeps gating correctly on `startsWith(head_ref,
+# 'release-please--')`.**
 
 "on":
   push:
@@ -28,9 +39,35 @@ concurrency:
 jobs:
   release-please:
     runs-on: ubuntu-latest
+    timeout-minutes: 10
     steps:
-      - uses: googleapis/release-please-action@45996ed1f6d02564a971a2fa1b5860e934307cf7 # v5.0.0
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+
+      - uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
         with:
-          token: ${{ secrets.GITHUB_TOKEN }}
-          config-file: release-please-config.json
-          manifest-file: .release-please-manifest.json
+          node-version: 20
+
+      # Phase A — open / update the release PR. Idempotent: re-runs
+      # on every push, only mutates GitHub when something changed.
+      - name: Update release PR
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          npx --yes release-please@17 release-pr \
+            --token="${GITHUB_TOKEN}" \
+            --repo-url="${GITHUB_REPOSITORY}" \
+            --config-file=release-please-config.json \
+            --manifest-file=.release-please-manifest.json
+
+      # Phase B — when the head commit IS the release PR's merge
+      # commit, cut the GitHub release + tag. No-op on every other
+      # push, so we can run both phases unconditionally.
+      - name: Publish GitHub release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          npx --yes release-please@17 github-release \
+            --token="${GITHUB_TOKEN}" \
+            --repo-url="${GITHUB_REPOSITORY}" \
+            --config-file=release-please-config.json \
+            --manifest-file=.release-please-manifest.json