docs: update README for v3.2.1 LoRA Manager integration (#52)
- Add LoRA Manager integration section with setup guide and CivitAI key docs
- Add folder filter section with rescan note for existing libraries
- Add v3.2.1 changelog entry, split from v3.2.0
- Add WIP notice for LoRA Manager feature
- Update AutoTag section to include WD14 models
- Fix stale references (KikoTextEncode, outdated file structure)
- Remove dated v2 development note
- Add screenshots for settings, integration, and filtered results
- Fix code review items: remove unused constant, add comments to empty excepts
- Bump version to 3.2.1