Assisted-by: GLM-5 via pi

diff --git a/.gitea/actions/setup-rust/action.yml b/.gitea/actions/setup-rust/action.yml
new file mode 100644
index 0000000..58279f2
--- /dev/null
+++ b/.gitea/actions/setup-rust/action.yml
@@ -0,0 +1,27 @@
+name: Setup Rust
+description: Install rustup, add cargo to PATH, and restore cargo cache
+
+inputs:
+  cache-key-suffix:
+    description: Suffix for the cache key (bump to force bust)
+    required: false
+    default: v1
+
+runs:
+  using: composite
+  steps:
+    - run: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+      shell: bash
+    - run: echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"
+      shell: bash
+    - uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4
+      with:
+        path: |
+          ~/.cargo/bin/
+          ~/.cargo/registry/index/
+          ~/.cargo/registry/cache/
+          ~/.cargo/git/db/
+          target/
+        # Bump suffix to force cache bust after upgrading installed tools.
+        key: cargo-${{ runner.os }}-${{ inputs.cache-key-suffix }}-${{ hashFiles('Cargo.lock') }}
+        restore-keys: cargo-${{ runner.os }}-${{ inputs.cache-key-suffix }}-
diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index f8b9f98..7ac1f4d 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -14,25 +14,21 @@ jobs:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
         with:
           persist-credentials: false
-
-      - run: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
-      - run: echo "$HOME/.cargo/bin" >> "$GITHUB_PATH"
-
-      - uses: actions/cache@1bd1e32a3bdc45362d1e726936510720a7c30a57 # v4
-        with:
-          path: |
-            ~/.cargo/bin/
-            ~/.cargo/registry/index/
-            ~/.cargo/registry/cache/
-            ~/.cargo/git/db/
-            target/
-          # Cache key is Cargo.lock, which means cargo install'ed tools (grcov, just)
-          # may be stale after a cache hit. Bump the suffix to force a cache bust.
-          key: cargo-${{ runner.os }}-v1-${{ hashFiles('Cargo.lock') }}
-          restore-keys: cargo-${{ runner.os }}-
-
+      - uses: ./.gitea/actions/setup-rust
       - run: rustup component add clippy rustfmt llvm-tools
       - run: cargo install grcov
       - run: cargo install just
       - run: cargo fmt --check
       - run: just clippy coverage
+
+  zizmor:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
+        with:
+          persist-credentials: false
+      - uses: ./.gitea/actions/setup-rust
+      # Can't use zizmorcore/zizmor-action because it doesn't support
+      # auditing .gitea/workflows/ — it rejects them as invalid inputs.
+      - run: cargo install --locked zizmor
+      - run: zizmor .gitea/workflows/* .github
diff --git a/.gitea/workflows/zizmor.yml b/.gitea/workflows/zizmor.yml
deleted file mode 100644
index 5b178f3..0000000
--- a/.gitea/workflows/zizmor.yml
+++ /dev/null
@@ -1,21 +0,0 @@
-name: Zizmor
-
-on:
-  push:
-    branches: [main]
-  pull_request:
-
-permissions: {}
-
-jobs:
-  zizmor:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
-        with:
-          persist-credentials: false
-      - uses: zizmorcore/zizmor-action@f52a838cfabf134edcbaa7c8b3677dde20045018 # v0.1.1
-        with:
-          inputs: .gitea/workflows/* .github
-          advanced-security: false
-          annotations: true