Add smoke tests for Chrome-based diagram rendering and update CI

Add smoke tests exercising mermaid and graphviz rendering through
chrome-headless-shell (PDF, Typst, multi-diagram). Remove not_os:linux
restrictions from existing mermaid SVG tests since Chrome is now
available on all CI platforms. Replace browser-actions/setup-chrome
with quarto install chrome-headless-shell in CI workflow.

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

Author: cderv

.github/workflows/test-smokes.yml

@@ -212,8 +212,11 @@ jobs:
         id: cache-typst
         uses: ./.github/actions/cache-typst
 
-      - name: Install Chrome
-        uses: browser-actions/setup-chrome@latest
+      - name: Install Chrome Headless Shell
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          quarto install chrome-headless-shell --no-prompt
 
       - name: Setup Julia
         uses: julia-actions/setup-julia@v2

tests/docs/smoke-all/2025/11/10/13661.qmd

@@ -12,8 +12,6 @@ format:
     use-rsvg-convert: false
 _quarto:
   tests:
-    run:
-      not_os: linux
     latex:
       printsMessage:
         level: INFO

tests/docs/smoke-all/2025/11/14/mermaid-svg-docx.qmd

@@ -5,8 +5,6 @@ format:
     mermaid-format: svg
 _quarto:
   tests:
-    run:
-      not_os: linux
     docx:
       printsMessage:
         level: INFO

tests/docs/smoke-all/2025/11/18/mermaid-gfm-svg.qmd

@@ -4,8 +4,6 @@ format: gfm
 mermaid-format: svg
 _quarto:
   tests:
-    run:
-      not_os: linux
     gfm:
       ensureFileRegexMatches:
         - ['img.*mermaid-figure-.*?\.svg']  # Verify markdown image link to SVG

tests/docs/smoke-all/2026/02/12/dot-pdf.qmd

@@ -0,0 +1,20 @@
+---
+title: "Graphviz to PDF (#11877)"
+format: pdf
+_quarto:
+  tests:
+    pdf:
+      noErrors: default
+---
+
+## Graphviz Diagram
+
+```{dot}
+digraph G {
+    A -> B
+    B -> C
+    B -> D
+    C -> E
+    D -> E
+}
+```

tests/docs/smoke-all/2026/02/12/mermaid-multi-diagram.qmd

@@ -0,0 +1,39 @@
+---
+title: "Multiple Mermaid Diagrams to PDF (#11877)"
+format: pdf
+_quarto:
+  tests:
+    pdf:
+      noErrors: default
+---
+
+## Flowchart
+
+```{mermaid}
+graph TD
+    A[Start] --> B{Decision}
+    B -->|Yes| C[Good]
+    B -->|No| D[Bad]
+    C --> E[End]
+    D --> E
+```
+
+## Sequence Diagram
+
+```{mermaid}
+sequenceDiagram
+    Alice->>Bob: Hello
+    Bob-->>Alice: Hi back
+    Alice->>Bob: How are you?
+    Bob-->>Alice: Good thanks
+```
+
+## Pie Chart
+
+```{mermaid}
+pie title Favorite Languages
+    "TypeScript" : 40
+    "Lua" : 30
+    "R" : 20
+    "Python" : 10
+```

tests/docs/smoke-all/2026/02/12/mermaid-pdf-default.qmd

@@ -0,0 +1,19 @@
+---
+title: "Mermaid to PDF (#11877)"
+format: pdf
+_quarto:
+  tests:
+    pdf:
+      noErrors: default
+---
+
+## Mermaid Flowchart
+
+```{mermaid}
+graph TD
+    A[Start] --> B{Decision}
+    B -->|Yes| C[Good]
+    B -->|No| D[Bad]
+    C --> E[End]
+    D --> E
+```

tests/docs/smoke-all/2026/02/12/mermaid-typst.qmd

@@ -0,0 +1,19 @@
+---
+title: "Mermaid to Typst (#11877)"
+format: typst
+_quarto:
+  tests:
+    typst:
+      noErrors: default
+---
+
+## Mermaid Flowchart
+
+```{mermaid}
+graph TD
+    A[Start] --> B{Decision}
+    B -->|Yes| C[Good]
+    B -->|No| D[Bad]
+    C --> E[End]
+    D --> E
+```