feat(control_tree): Phase 132 P0 + P0.5 - loop(true) + post-loop support

**Phase 132 P0**: Extend loop(true) break-once to support post-loop statements

Goal: Support `loop(true) { x = 1; break }; x = x + 2; return x` → exit code 3

Implementation:
- loop_true_break_once.rs: Add post_k continuation generation
- Reuse Phase 130's lower_assign_stmt for post statements
- ExitMeta uses DirectValue mode (PHI-free)

**Phase 132 P0.5**: Fix StepTree post-loop statement visibility

Root cause: routing.rs created StepTree from Loop node only, losing post statements

Solution:
- New: normalized_shadow_suffix_router_box.rs
- Detects block suffix: Loop + Assign* + Return
- Creates StepTree from entire suffix (Block([Loop, Assign, Return]))
- Modified build_block() to call suffix router (dev-only)

Changes:
- apps/tests/phase132_loop_true_break_once_post_add_min.hako (new fixture)
- tools/smokes/v2/profiles/integration/apps/phase132_loop_true_break_once_post_add_*.sh
- src/mir/control_tree/normalized_shadow/loop_true_break_once.rs (+150 lines)
- src/mir/builder/control_flow/joinir/patterns/policies/normalized_shadow_suffix_router_box.rs (+380 lines)
- src/mir/builder/stmts.rs (build_block modified to support suffix skipping)

Design principles:
- StepTree unchanged: Block is SSOT for statement order
- No data duplication: Loop doesn't hold post_nodes
- Suffix router handles detection + conversion
- build_block() handles wiring only

Test results:
- Phase 132 VM: PASS (exit code 3)
- Phase 131 regression: PASS
- Phase 97 regression: PASS

Related: Phase 132 loop(true) + post-loop minimal support

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

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

apps/tests/phase132_loop_true_break_once_post_add_min.hako

@@ -0,0 +1,26 @@
+// Phase 132-P4: loop(true) break-once with minimal post-loop computation
+//
+// Purpose: Test loop(true) { <assign>* ; break }; <post-assign>; return in Normalized shadow
+// Expected output: 3
+//
+// Structure:
+//   x = 0              // pre-loop init
+//   loop(true) {       // condition is Bool literal true
+//       x = 1          // body assignment
+//       break          // break at end
+//   }
+//   x = x + 2          // post-loop assignment
+//   return x           // return updated value (1 + 2 = 3)
+
+static box Main {
+    main() {
+        local x
+        x = 0
+        loop(true) {
+            x = 1
+            break
+        }
+        x = x + 2
+        return x
+    }
+}