ci(docs[builder]): Switch sphinx build from html to dirhtml

why: CloudFront is configured with the dirhtml_clean_urls function
     (same as libtmux/tmuxp); building with -b html produces .html files
     that the CF function tries to redirect away from
what:
- Change sphinx-build -b html to -b dirhtml in docs publish step

Author: tony

.github/workflows/docs.yml

@@ -69,7 +69,7 @@ jobs:
 
       - name: Build documentation
         if: steps.changes.outputs.publishable == 'true'
-        run: uv run sphinx-build -W -b html docs docs/_build/html
+        run: uv run sphinx-build -W -b dirhtml docs docs/_build/html
 
       - name: Configure AWS Credentials
         if: steps.changes.outputs.publishable == 'true'