refactor(mir): Phase 139-P3-B - RoutingDecision を enum 対応 + レガシー削除

- RoutingDecision の missing_caps を Vec<CapabilityTag> に変更（型安全化）
- error_tags は to_tag() メソッドで自動生成
- 全 callsite を enum variant に修正
- capability_tags モジュール（文字列定数群）を完全削除
- 全テスト PASS（型安全性向上を確認）
- フォーマット適用

src/mir/join_ir/lowering/expr_lowerer.rs

@@ -192,7 +192,11 @@ impl<'env, 'builder, S: ScopeManager> ExprLowerer<'env, 'builder, S> {
         // 2. Build ConditionEnv from ScopeManager
         // Phase 79-1: Use BindingId-aware version when available
         #[cfg(feature = "normalized_dev")]
-        let condition_env = scope_resolution::build_condition_env_from_scope_with_binding(self.scope, ast, self.builder)?;
+        let condition_env = scope_resolution::build_condition_env_from_scope_with_binding(
+            self.scope,
+            ast,
+            self.builder,
+        )?;
 
         #[cfg(not(feature = "normalized_dev"))]
         let condition_env = scope_resolution::build_condition_env_from_scope(self.scope, ast)?;
@@ -279,13 +283,17 @@ impl<'env, 'builder, S: ScopeManager> ConditionLoweringBox<S> for ExprLowerer<'e
 
         // Build ConditionEnv from the provided scope (the caller controls the scope + allocator).
         #[cfg(feature = "normalized_dev")]
-        let condition_env =
-            scope_resolution::build_condition_env_from_scope_with_binding(context.scope, condition, self.builder)
-                .map_err(|e| e.to_string())?;
+        let condition_env = scope_resolution::build_condition_env_from_scope_with_binding(
+            context.scope,
+            condition,
+            self.builder,
+        )
+        .map_err(|e| e.to_string())?;
 
         #[cfg(not(feature = "normalized_dev"))]
-        let condition_env = scope_resolution::build_condition_env_from_scope(context.scope, condition)
-            .map_err(|e| e.to_string())?;
+        let condition_env =
+            scope_resolution::build_condition_env_from_scope(context.scope, condition)
+                .map_err(|e| e.to_string())?;
 
         // Delegate to the well-tested lowerer, but use the caller-provided allocator (SSOT).
         let (result_value, instructions) =
@@ -347,7 +355,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };
 
@@ -393,7 +401,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };
 
@@ -439,7 +447,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };
 
@@ -521,7 +529,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };
         let boxed_carrier: Box<CarrierInfo> = Box::new(carrier_info);
@@ -550,7 +558,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };
         let boxed_carrier: Box<CarrierInfo> = Box::new(carrier_info);
@@ -701,7 +709,7 @@ mod tests {
             carriers: vec![],
             trim_helper: None,
             promoted_loopbodylocals: vec![],
-#[cfg(feature = "normalized_dev")]
+            #[cfg(feature = "normalized_dev")]
             promoted_bindings: std::collections::BTreeMap::new(),
         };