fix: fix cache path, HTML job dependency, and job names

- HTML builds no longer wait for setup-latex-cache since they don't need LaTeX
- PDF builds still depend on setup-latex-cache
- Job names are now "Building <manual> HTML" and "Building <manual> PDF"
- Cache path changed from ~/.cache/texlive-fonts-extra to
  ${{ github.workspace }}/.cache/texlive-fonts-extra so the tar archive
  stores a workspace-relative path that resolves to the same location on
  both GitHub-hosted and self-hosted runners (the old ~ path was encoded
  as ../../../.cache/... relative to the workspace root, which resolved
  to different absolute paths depending on the runner's directory depth)

Agent-Logs-Url: https://github.com/nextcloud/documentation/sessions/80b5c006-0eb9-4931-950f-5dec3be72077

Co-authored-by: skjnldsv <14975046+skjnldsv@users.noreply.github.com>

Author: Copilot

.github/workflows/sphinxbuild.yml

@@ -25,7 +25,7 @@ jobs:
         id: cache-fonts-extra
         uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
         with:
-          path: ~/.cache/texlive-fonts-extra
+          path: ${{ github.workspace }}/.cache/texlive-fonts-extra
           key: latex-fonts-extra-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023-v1
           lookup-only: true
 
@@ -39,27 +39,26 @@ jobs:
             sleep 15
           done
           sudo DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends texlive-fonts-extra
-          mkdir -p ~/.cache/texlive-fonts-extra
+          mkdir -p "$GITHUB_WORKSPACE/.cache/texlive-fonts-extra"
           while IFS= read -r f; do
             [ -f "$f" ] || [ -L "$f" ] || continue
             rel="${f#/}"
-            dir="$HOME/.cache/texlive-fonts-extra/$(dirname "$rel")"
+            dir="$GITHUB_WORKSPACE/.cache/texlive-fonts-extra/$(dirname "$rel")"
             mkdir -p "$dir"
             sudo cp -P "$f" "$dir/"
           done < <(dpkg -L texlive-fonts-extra)
-          sudo chown -R $(id -u):$(id -g) ~/.cache/texlive-fonts-extra
+          sudo chown -R $(id -u):$(id -g) "$GITHUB_WORKSPACE/.cache/texlive-fonts-extra"
 
       - name: Save texlive-fonts-extra installed files cache (cache miss only)
         if: steps.cache-fonts-extra.outputs.cache-hit != 'true'
         uses: actions/cache/save@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
         with:
-          path: ~/.cache/texlive-fonts-extra
+          path: ${{ github.workspace }}/.cache/texlive-fonts-extra
           key: latex-fonts-extra-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023-v1
 
   build-html:
-    name: Build ${{ matrix.manual.name }}
+    name: Building ${{ matrix.manual.name }} HTML
     runs-on: ubuntu-latest
-    needs: setup-latex-cache
 
     strategy:
       fail-fast: false
@@ -115,7 +114,7 @@ jobs:
   # BUILD PDF
   # ============================================================================
   build-pdf:
-    name: Build PDF ${{ matrix.manual.name }}
+    name: Building ${{ matrix.manual.name }} PDF
     runs-on: [ubuntu-latest, self-hosted]
     needs: setup-latex-cache
 
@@ -146,12 +145,12 @@ jobs:
       - name: Restore texlive-fonts-extra installed files
         uses: actions/cache/restore@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
         with:
-          path: ~/.cache/texlive-fonts-extra
+          path: ${{ github.workspace }}/.cache/texlive-fonts-extra
           key: latex-fonts-extra-${{ runner.os }}-${{ runner.arch }}-ubuntu-24.04-texlive-2023-v1
           fail-on-cache-miss: true
 
       - name: Install texlive-fonts-extra from cache
-        run: sudo cp -r ~/.cache/texlive-fonts-extra/. /
+        run: sudo cp -r "$GITHUB_WORKSPACE/.cache/texlive-fonts-extra/." /
 
       - name: Install LaTeX packages
         run: |