feat(guide): add Production Safety Rules (v3.9.11)

Add comprehensive production safety guide for teams deploying Claude Code in production environments with 6 critical rules:

- Port Stability: Prevent accidental port changes breaking configs
- Database Safety: Backup enforcement via PreToolUse hooks
- Feature Completeness: No TODOs for core functionality
- Infrastructure Lock: Protect docker-compose, Dockerfile, terraform
- Dependency Safety: Block unapproved npm packages
- Pattern Following: Enforce codebase conventions

Adapted from community "10 non-negotiable CLAUDE.md rules" (6/10 integrated, 4/10 already covered). Verified gaps using grepai searches. Target audience: 20% production teams.

Cross-references added in ultimate-guide.md (section 3.1) and adoption-approaches.md (Medium/Large teams).

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

guide/ultimate-guide.md

@@ -10,7 +10,7 @@
 
 **Last updated**: January 2026
 
-**Version**: 3.9.9
+**Version**: 3.9.11
 
 ---
 
@@ -3416,6 +3416,10 @@ Express + Prisma backend.
 - Prisma queries in /repositories
 ```
 
+**Production Safety**: For teams deploying Claude Code in production, see [Production Safety Rules](production-safety.md) for port stability, database safety, and infrastructure lock patterns.
+
+---
+
 ## 3.2 The .claude/ Folder Structure
 
 The `.claude/` folder is your project's Claude Code directory for memory, settings, and extensions.
@@ -11553,4 +11557,4 @@ Thumbs.db
 
 **Contributions**: Issues and PRs welcome.
 
-**Last updated**: January 2026 | **Version**: 3.9.9
+**Last updated**: January 2026 | **Version**: 3.9.11