Rename project to SSAU Generator and restructure content

- Move projects into content/<project>/{docx,pptx} with shared assets/
- Flatten config paths; output = project name in project folder
- Add pptx --init scaffold; remove docx exe build
- Add feature-complete content/example; ignore content/* except example
- Rewrite README and AGENTS.md

pptx/src/plantuml.js

@@ -114,7 +114,7 @@ function cacheFileName(sourceBuffer, cfg) {
 }
 
 async function renderCached(sourceBuffer, cfg) {
-  const dir = cfg.cacheDir || path.join(os.tmpdir(), "lab-gen-pptx-plantuml");
+  const dir = cfg.cacheDir || path.join(os.tmpdir(), "ssau-generator-pptx-plantuml");
   const target = path.join(dir, cacheFileName(sourceBuffer, cfg));
 
   if (cfg.cache && fs.existsSync(target)) {