Initial release: Citrine v1.0.0

Minimalist plaintext project-based todo CLI in Rust.
Commands: init, add, list, set, done, rm.
Supports .citrine + .citrine.local merging, partial hash matching,
status filtering, and colorized output.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/fixtures/sample.citrine

@@ -0,0 +1,9 @@
+## Backend
+[a4f9] [ ] Implement caching layer @priority:high @backend
+[b2e1] [>] Refactor auth module @assigned:cursor
+[c3d8] [-] Deploy to staging @blocked:waiting-for-credentials
+[f1a2] [x] Set up Docker config @completed:2025-02-14
+
+## Frontend
+[d4b3] [ ] Build settings page
+[e5c2] [>] Fix mobile layout issues @priority:medium