perf(ci): optimize latex caching

Signed-off-by: skjnldsv <skjnldsv@protonmail.com>

Author: skjnldsv

.github/workflows/sphinxbuild.yml

@@ -34,6 +34,7 @@ jobs:
           restore-keys: |
             latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-
             latex-apt-${{ runner.os }}-${{ runner.arch }}-
+          lookup-only: true
 
       - name: Download LaTeX packages (cache miss only)
         if: steps.cache-latex-apt.outputs.cache-hit != 'true'
@@ -47,6 +48,13 @@ jobs:
           # Ensure downloaded packages are owned by the current user so they can be cached
           sudo chown -R $(id -u):$(id -g) ${{ runner.temp }}/.cache/archives
 
+      - name: Save LaTeX apt cache (cache miss only)
+        if: steps.cache-latex-apt.outputs.cache-hit != 'true'
+        uses: actions/cache/save@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
+        with:
+          path: ${{ runner.temp }}/.cache/archives
+          key: latex-apt-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023
+
   build:
     name: Build ${{ matrix.manual.name }}
     runs-on: ubuntu-latest
@@ -410,7 +418,7 @@ jobs:
   deploy:
     name: Deploy documentation for gh-pages
     needs: stage-and-check
-    if: github.event_name == 'push'
+    if: always()
     runs-on: ubuntu-latest
 
     permissions:
@@ -495,14 +503,17 @@ jobs:
         if: steps.apply.outputs.has_changes == 'true'
         with:
           token: ${{ secrets.COMMAND_BOT_PAT }}
-          commit-message: "chore: update documentation for ${{ needs.stage-and-check.outputs.branch_name }}"
+          commit-message: "chore: update documentation for `${{ needs.stage-and-check.outputs.branch_name }}`"
           committer: nextcloud-command <nextcloud-command@users.noreply.github.com>
           author: nextcloud-command <nextcloud-command@users.noreply.github.com>
           signoff: true
           branch: "automated/deploy/documentation-${{ needs.stage-and-check.outputs.branch_name }}"
           base: gh-pages
-          title: "Documentation update for ${{ needs.stage-and-check.outputs.branch_name }}"
-          body: "Automated documentation update from branch ${{ github.ref_name }}"
+          title: "Documentation update for `${{ needs.stage-and-check.outputs.branch_name }}`"
+          body: |
+            This PR was automatically generated by the CI workflow and
+            includes the latest changes for the `${{ needs.stage-and-check.outputs.branch_name }}` branch.
+
           delete-branch: true
           labels: "automated, 3. to review"