ci: publish to crates.io by OIDC instead of a personal API token

.github/workflows/release.yml

@@ -84,8 +84,20 @@ jobs:
     needs: [crate, wheels, pypi]
     if: startsWith(github.ref, 'refs/tags/') && github.repository_owner == 'IntelliStream-DataHub'
     environment: release
+    # Job-level permissions replace the workflow's `contents: read` wholesale, so it is repeated
+    # here alongside the OIDC claim the auth action needs; without it `checkout` has no scope.
+    permissions:
+      contents: read
+      id-token: write
     steps:
       - uses: actions/checkout@v6
+      # Trades this run's OIDC identity for a crates.io token scoped to this crate and revoked in
+      # the action's post step, so no long-lived credential exists to leak or to expire. Requires
+      # a Trusted Publisher registered on the crate naming this repository, workflow and
+      # environment; crates.io only accepts one on a crate that already has a published version,
+      # which is why this could not be set up before 0.2.0 went out.
+      - uses: rust-lang/crates-io-auth-action@v1
+        id: auth
       - run: cargo publish
         env:
-          CARGO_REGISTRY_TOKEN: ${{ secrets.CARGO_REGISTRY_TOKEN }}
+          CARGO_REGISTRY_TOKEN: ${{ steps.auth.outputs.token }}