feat(frontend): auto-derive slugs from names on create forms (#48)

The org/project/bucket/collection create forms required typing a slug
by hand. While the slug field is untouched (empty or still equal to the
derived value), naming the entity fills its slug; a manual slug edit
stops the derivation and is sanitized to slug form as you type.

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

CHANGELOG.md

@@ -4,6 +4,10 @@ All notable changes to Primora. Format follows [Keep a Changelog](https://keepac
 
 ## [Unreleased]
 
+### Added
+
+- **Slugs auto-derive from names** — typing an organization, project, bucket, or collection name now fills its slug (`TDvorak` → `tdvorak`); hand-editing the slug stops the derivation, and manual edits are sanitized as you type. Edit forms stay manual.
+
 ## [0.8.3] - 2026-09-28
 
 ### Added