fix(ci): replace JS-based actions with shell equivalents for host-mode runner

actions/checkout and actions/setup-dotnet are JavaScript actions, and act's
host execution mode has a known unfixed path-resolution bug that causes
MODULE_NOT_FOUND on their dist/index.js (nektos/act#2024). Replace them with
plain git/dotnet shell steps that work against the runner's pre-installed
toolchain.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/release.yml

@@ -3,11 +3,17 @@ name: Publish Release
 # NOTE: This repo lives on a private Gitea instance
 # (https://www.git.quarantinedstudio.com/mvezina/CinemaTrailers4Jellyfins), not GitHub.
 # Gitea Actions understands a compatible subset of GitHub Actions syntax, but:
-#   - GitHub-hosted actions (actions/checkout, actions/setup-dotnet) must be reachable
-#     from your Gitea runner (directly, via a mirror, or vendored) to be usable as-is.
+#   - The runner here executes jobs in host mode (no Docker). act's host executor has
+#     a known unfixed path-resolution bug for JavaScript-based actions (MODULE_NOT_FOUND
+#     on dist/index.js — see nektos/act#2024), so actions/checkout and
+#     actions/setup-dotnet are replaced below with plain git/shell equivalents. The
+#     runner host already has git, dotnet (9.x), zip/unzip and python3+pyyaml installed.
 #   - softprops/action-gh-release talks to the GitHub API and will NOT work against
 #     Gitea — it has been replaced below with direct calls to the Gitea Releases API
-#     via curl, which needs a GITEA_TOKEN secret (an access token with repo write scope).
+#     via curl, which needs a GITEA_TOKEN secret. Note: GITEA_TOKEN is a *reserved* name
+#     that Gitea auto-injects into every job (like GitHub's GITHUB_TOKEN) — you cannot
+#     and do not need to create it yourself; its permissions come from the `permissions:`
+#     block below.
 # Treat this file as a starting template: verify runner/action availability and the
 # release-API calls against your instance before relying on it.
 
@@ -25,15 +31,22 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
-        with:
-          token: ${{ secrets.GITEA_TOKEN }}
-          fetch-depth: 0
+        env:
+          GITEA_TOKEN: ${{ secrets.GITEA_TOKEN }}
+        run: |
+          set -e
+          REPO_URL="${{ github.server_url }}/${{ github.repository }}.git"
+          AUTH_HEADER="$(printf 'x-access-token:%s' "$GITEA_TOKEN" | base64 -w0)"
+          git init -q .
+          git remote add origin "$REPO_URL"
+          git config http.extraheader "Authorization: Basic ${AUTH_HEADER}"
+          git fetch -q origin "${{ github.ref }}"
+          git checkout -q FETCH_HEAD
+          git config user.name "gitea-actions"
+          git config user.email "gitea-actions@quarantinedstudio.com"
 
-      - name: Setup .NET 9
-        uses: actions/setup-dotnet@v4
-        with:
-          dotnet-version: '9.0.x'
+      - name: Verify .NET 9 SDK
+        run: dotnet --version
 
       - name: Get version from tag
         id: version