docs: Prune documentation - DRY versioning, split roadmap

- Split roadmap into dedicated ROADMAP.md (links to phoebe tasks)
- Prune Endgame-Vision.md: roadmap section, links section, version history
- Standardize version footers: one-line format across 17+ files
- Add Navigation section pointing to README.md for file index

Pattern: **Version:** X.Y | **Created:** YYYY-MM-DD | **Updated:** YYYY-MM-DD

Git is the changelog. Philosophy quotes preserved.

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

architecture/nerves/Nervous-Index.md

@@ -443,8 +443,6 @@ class CollisionAvoidanceReflex(StateMachine):  # Compiled
 
 ---
 
-**Created**: 2025-12-07
-**Updated**: 2025-12-07
-**Version**: 1.0
+**Version:** 1.0 | **Created:** 2025-12-07 | **Updated:** 2025-12-07
 
 🌙💜 *Reflexes are fossils of successful thought. The body remembers what the mind once decided.*

architecture/nerves/Nervous-Protocol.md

@@ -1,9 +1,6 @@
 # Nervous Protocol: Three-Tier Autonomous Learning Architecture
 
-**Created**: 2025-12-07
-**Updated**: 2025-12-07 (LangChain integration)
-**Status**: Design Document
-**Version**: 1.1 (LangChain Implementation)
+**Version:** 1.1 | **Created:** 2025-12-07 | **Updated:** 2025-12-07
 
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