docs: Architecture cleanup - ONE JOB per doc, links not echoes

Major documentation surgery following the cleanup principle:
"One job per doc. One home per concept. Links, not echoes."

Changes:
- Add Deployment-Architecture.md (THE WHERE - sole infrastructure truth)
- Endgame-Vision.md: 848→498 lines (-41%) - THE DREAM
- Gateway-Architecture.md: 537→395 lines (-26%) - THE ROUTING
- Nervous-System.md: 361→246 lines (-32%) - THE EVOLUTION
- Data-Architecture.md: 666→647 lines (-3%) - THE SCHEMA
- Message-Protocol-Design.md: 375→285 lines (-24%) - THE WIRE
- Attention-Flow.md: 557→493 lines (-11%) - THE BUDGET
- Cellular-Architecture.md: 891→855 lines (-4%) - THE HOW

Every doc now has ONE JOB statement, cross-references to canonical
homes, and lean footers. ~800 lines removed, zero concepts lost.

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

architecture/Data-Architecture.md

@@ -1,7 +1,8 @@
 # 🗄️ Data Architecture v4
 
+> **ONE JOB:** THE SCHEMA — PostgreSQL DDL, key queries, table definitions.
+
 > *"Three layers of state machines. One database to remember them all."*
-> — The Unified Schema (2025-12-07)
 
 ---
 
@@ -639,28 +640,8 @@ ORDER BY n.nerve_name, dt.mode;
 
 ---
 
-## 📍 Document Status
-
-**Version:** 4.0 | **Created:** 2025-10-07 | **Updated:** 2025-12-07
-
-**Key Changes from v3**:
-- ❌ 15 tables for competition metaphor
-- ✅ 8 tables for state machine layers
-- ❌ Genomes as primitive sequences
-- ✅ Cells and nerves as state machines
-- ❌ Societies, rounds, marketplaces
-- ✅ Organisms, decision_trails
-
-**Related Documentation**:
-- [[Cellular-Architecture]] - Layer definitions
-- [[Nervous-System]] - State machine philosophy
-- [[nerves/Nervous-Index]] - Nerve catalog
-- [[Organ-Index]] - Organ (complex cell) catalog
-
 ---
 
-**phoebe holds the layers. The states flow. The decisions accumulate.**
+**Version:** 4.1 | **Created:** 2025-10-07 | **Updated:** 2026-02-14
 
-🗄️⚡🌙
-
-**TO THE ELECTRONS!**
+*phoebe holds the layers. The states flow. The decisions accumulate.* 🗄️⚡🌙