fix(ci): install protoc for the release build, and allow republishing a tag

.github/workflows/release.yml

@@ -11,6 +11,21 @@ name: Release
 on:
   push:
     branches: [main]
+  # Recovery path. A release tag is created by the job below and only that run
+  # carries `release_created`, so a publish that fails for a reason outside the
+  # tag — a missing tool on the runner, a registry outage — cannot be retried by
+  # re-running it: the re-run replays the workflow file of that commit, which is
+  # the one that failed.
+  #
+  # Dispatch this **with the release tag selected as the ref**, not from a
+  # branch with the tag as a parameter. Taking it as a free-form input would let
+  # a dispatch publish any branch or commit through a job holding npm OIDC
+  # rights, and npm's provenance records the event's ref and sha rather than
+  # whatever the workspace was checked out to — so a tarball built from a tag
+  # while the event pointed at a branch would be attested to the wrong commit.
+  # The ref picker only offers refs that exist, and `ref_type` below rejects
+  # everything that is not a tag.
+  workflow_dispatch:
 
 permissions:
   contents: read
@@ -26,6 +41,7 @@ env:
 jobs:
   release-please:
     name: Prepare release
+    if: github.event_name == 'push'
     runs-on: ubuntu-latest
     timeout-minutes: 10
     permissions:
@@ -77,17 +93,46 @@ jobs:
   verify:
     name: Verify the tag
     needs: release-please
-    if: needs.release-please.outputs.release_created == 'true'
+    # `!cancelled()` rather than `always()`: the dispatch path needs this to run
+    # past a skipped release-please, but a cancelled run must not go on to
+    # publish.
+    if: >-
+      !cancelled() &&
+      (needs.release-please.outputs.release_created == 'true' ||
+       (github.event_name == 'workflow_dispatch' && github.ref_type == 'tag'))
     runs-on: ubuntu-latest
     timeout-minutes: 45
     permissions:
       contents: read
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
-          ref: ${{ needs.release-please.outputs.tag_name }}
+          # The commit the event recorded, never a ref. A ref can move between
+          # the event and either checkout, and npm records this sha as the
+          # package's source regardless of what the workspace holds — so
+          # resolving a tag here could publish one tree while attesting another.
+          ref: ${{ github.sha }}
           persist-credentials: false
 
+      # Guards the assumption on the push path: release-please tags the commit
+      # it just merged, so a tag pointing elsewhere means this run would verify
+      # and publish something the release does not name.
+      - name: Confirm the release tag points at this commit
+        if: github.event_name == 'push'
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          TAG: ${{ needs.release-please.outputs.tag_name }}
+        run: |
+          ref=$(gh api "repos/$GITHUB_REPOSITORY/git/ref/tags/$TAG")
+          target=$(jq -r '.object.sha' <<<"$ref")
+          if [ "$(jq -r '.object.type' <<<"$ref")" = tag ]; then
+            target=$(gh api "repos/$GITHUB_REPOSITORY/git/tags/$target" --jq '.object.sha')
+          fi
+          if [ "$target" != "$GITHUB_SHA" ]; then
+            echo "::error::$TAG points at $target, not $GITHUB_SHA"
+            exit 1
+          fi
+
       - name: Install Rust
         uses: dtolnay/rust-toolchain@6c977a6ca4077a0ceb28ffbe03f59d46e9ac8772 # master
         with:
@@ -100,7 +145,9 @@ jobs:
       - name: Install wasm-pack
         uses: taiki-e/install-action@91ddec75689c4c78665b598d188dc821c5a43e5c # v2.85.9
         with:
-          tool: wasm-pack
+          # protoc: `bun run build` regenerates the proto codec, which ci.yml
+          # never exercises because it calls wasm-pack and build:ts directly.
+          tool: wasm-pack,protoc
 
       - uses: oven-sh/setup-bun@0c5077e51419868618aeaa5fe8019c62421857d6 # v2.2.0
         with:
@@ -131,7 +178,7 @@ jobs:
   publish:
     name: Publish to npm
     needs: [release-please, verify]
-    if: needs.release-please.outputs.release_created == 'true'
+    if: ${{ !cancelled() && needs.verify.result == 'success' }}
     runs-on: ubuntu-latest
     timeout-minutes: 45
     # Gate for the publish step: add required reviewers here to make releases
@@ -145,7 +192,8 @@ jobs:
     steps:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
         with:
-          ref: ${{ needs.release-please.outputs.tag_name }}
+          # Same immutable commit verify checked out and vouched for.
+          ref: ${{ github.sha }}
           # Nothing here talks to the remote after checkout, and the steps below
           # run cargo, bun and third-party build scripts in a job holding OIDC
           # publish rights. Don't leave the token in .git/config for them.
@@ -163,7 +211,9 @@ jobs:
       - name: Install wasm-pack
         uses: taiki-e/install-action@91ddec75689c4c78665b598d188dc821c5a43e5c # v2.85.9
         with:
-          tool: wasm-pack
+          # protoc: `bun run build` regenerates the proto codec, which ci.yml
+          # never exercises because it calls wasm-pack and build:ts directly.
+          tool: wasm-pack,protoc
 
       # Pinned, unlike ci.yml: this bun builds the wasm artifact that ships to
       # npm, so a floating version would change the published bytes without a