Cleaner generation recovery and template browsing

SlideDrift now handles in-progress generation placeholders more carefully.

If a carousel is opened while generation is still finishing, loading placeholders are treated as temporary content instead of finished slide text. Interrupted generations can resume when the deck still contains placeholder text, and generated rich text is synced before the finished slides are saved.

The Templates page is also easier to browse. Saved templates now load into My Templates separately from the public system catalog, and profession-specific templates are grouped by shared visual style instead of showing every story variation as a separate top-level card.

Published profession template pages can now point to related story variations and nearby styles, so you can keep a visual direction while switching to a different angle or story structure.