feat(joinir): Phase 191 body-local init integration into Pattern2

- Integrated LoopBodyLocalInitLowerer into Pattern2 lowering
- Fixed ValueId double-allocation issue (delegate to InitLowerer)
- Added body_ast parameter to lower_loop_with_break_minimal()
- Fixed json_program_loop.rs test for body-local scope
- New test: phase191_body_local_atoi.hako (expected: 123)

Supported init expressions:
- Integer literals, variable references, binary operations

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

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

src/mir/builder/control_flow/joinir/patterns/pattern2_with_break.rs

@@ -154,16 +154,13 @@ impl MirBuilder {
             id
         };
 
-        // Phase 185-2: Collect body-local variables with safe ValueId allocation
+        // Phase 191: Create empty body-local environment
+        // LoopBodyLocalInitLowerer will populate it during init lowering
         use crate::mir::join_ir::lowering::loop_body_local_env::LoopBodyLocalEnv;
-        let body_locals = collect_body_local_variables(_body, &mut alloc_body_local_value);
-        let body_local_env = LoopBodyLocalEnv::from_locals(body_locals);
+        let mut body_local_env = LoopBodyLocalEnv::new();
 
-        eprintln!("[pattern2/body-local] Phase 185-2: Collected {} body-local variables (offset={})",
-            body_local_env.len(), body_local_start_offset);
-        for (name, vid) in body_local_env.iter() {
-            eprintln!("  {} → {:?}", name, vid);
-        }
+        eprintln!("[pattern2/body-local] Phase 191: Created empty body-local environment (offset={})",
+            body_local_start_offset);
 
         // Create allocator for other JoinIR-local ValueIds (Trim pattern, etc.)
         // Continues from where body_local_counter left off
@@ -307,7 +304,8 @@ impl MirBuilder {
             &env,
             &carrier_info,
             &carrier_updates,
-            Some(&body_local_env),  // Phase 185-2: Pass body-local environment
+            _body,  // Phase 191: Pass body AST for init lowering
+            Some(&mut body_local_env),  // Phase 191: Pass mutable body-local environment
         ) {
             Ok((module, meta)) => (module, meta),
             Err(e) => {