docs(phase93): Phase 93 P0完了記録 & ドキュメント整理

## 追加
- docs/development/current/main/phases/phase-93/README.md
  - Phase 93 P0 (ConditionOnly Derived Slot) 完了記録
  - 実装内容・テスト結果の詳細

## 更新
- CURRENT_TASK.md: Phase 93 P0完了に伴う更新
- 10-Now.md: 現在の進捗状況更新
- 30-Backlog.md: Phase 92/93関連タスク整理
- phase-91/92関連ドキュメント: historical化・要約化

## 削減
- 735行削減（historical化により詳細をREADMEに集約）

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docs/development/current/main/design/pattern-p5b-escape-design.md

@@ -218,8 +218,8 @@ If any of these are detected, Pattern P5b is rejected:
 4. **Find process block**: `out = out + ch`
 5. **Find normal increment**: `i = i + 1` after if
 6. **Find break condition**: `if ch == "\"" { break }`
-7. **Build ExitContract** with both deltas
-8. **Build RoutingDecision**: Pattern5bEscape if all present
+7. **Build LoopSkeleton**: `UpdateKind::ConditionalStep { cond, then_delta, else_delta }` を構築
+8. **Build RoutingDecision**: `chosen = Pattern2Break`（exit contract 優先）。P5b 固有の構造情報は `notes` に載せる
 
 ### Pseudo-Code
 
@@ -305,8 +305,12 @@ LoopSkeleton {
     carriers: vec![
         CarrierSlot {
             name: "i",
-            deltas: [1, 2],  // [normal, escape]
-            // ... other fields
+            update_kind: UpdateKind::ConditionalStep {
+                cond: (ch == "\\"),
+                then_delta: 2,
+                else_delta: 1,
+            },
+            // ... other fields（role など）
         },
         CarrierSlot {
             name: "out",
@@ -328,7 +332,7 @@ LoopSkeleton {
 
 ```rust
 RoutingDecision {
-    chosen: Pattern5bEscape,
+    chosen: Pattern2Break,
     missing_caps: vec![],
     notes: vec![
         "escape_char: \\",