feat: enable text auto-wrap for text boxes by default

- Set text_frame.word_wrap = True in add_text_element() for PPTX
- Change CSS from white-space: pre-wrap to normal in HTML preview
- Add overflow-wrap: break-word for better word breaking
- Update README.md with auto-wrap documentation
- Update element-rendering and html-rendering specs
- Archive change: 2026-03-02-add-text-auto-wrap

.gitignore

@@ -262,3 +262,6 @@ pnpm-lock.yaml
 # !templates/
 # !examples/
 # !assets/
+
+
+temp