Update cc-rules.md: GitHub is source of truth

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/navi/cc-rules.md

@@ -10,6 +10,31 @@
 
 **Never touch:** `/home/zvx/projects/navi-work` on cortex (stale clone, do not use)
 
+## Git / Repository Rules
+
+**GitHub (zvx-echo6) is the source of truth for all repos.**
+
+### Remote Convention
+
+- **origin** = GitHub (github.com/zvx-echo6/{repo})
+- **forge** = Forgejo backup (forge.echo6.co/matt/{repo})
+
+### Creating New Repos
+
+1. Create on GitHub first (public unless told otherwise)
+2. Create matching repo on Forgejo
+3. Configure Forgejo repo as pull mirror from GitHub (8h interval)
+4. Local clone: origin = GitHub, forge = Forgejo
+
+### Exceptions
+
+- **echo6-docs** is the sole exception — Forgejo only, no GitHub copy
+
+### Rules
+
+- Never force-push to origin without explicit approval
+- Never use `git add -A` — stage files explicitly
+
 ## Critical Constraints
 
 - **Never re-export namedTheme** through any intermediary module — import directly from protomaps-themes-base in MapView.jsx