ci(docs): merge man-page and html-docs workflows into build-docs

Both workflows triggered on the same path change, installed pandoc
separately, and raced to commit — the second always failed on push
due to new commits from the first. A single job installs pandoc once,
generates both outputs, and commits them together.

.gitea/workflows/build-docs.yml

@@ -0,0 +1,45 @@
+name: Generate documentation
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "docs/fish-config.md"
+
+jobs:
+  build-docs:
+    runs-on: racknerd-mini
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          token: ${{ secrets.GITEA_TOKEN }}
+
+      - name: Install pandoc
+        run: sudo apt-get update -qq && sudo apt-get install -y pandoc
+
+      - name: Compile man page
+        run: |
+          pandoc --standalone \
+                 --from markdown \
+                 --to man \
+                 docs/fish-config.md \
+                 -o docs/fish-config.1
+
+      - name: Generate chunked HTML docs
+        run: |
+          rm -rf docs/html/
+          pandoc -f gfm -t chunkedhtml --split-level=1 --toc \
+                 --include-in-header docs/html-style.html \
+                 docs/fish-config.md \
+                 -o docs/html/
+
+      - name: Commit generated docs
+        run: |
+          git config user.name  "Gitea Actions"
+          git config user.email "actions@gitea"
+          git add docs/fish-config.1 docs/html/
+          git diff --cached --quiet && echo "No changes to commit" && exit 0
+          git commit -m "chore(docs): regenerate man page and HTML docs"
+          git push