test(phase263): add minimal repro for Pattern2 LoopBodyLocal seg issue

- apps/tests/phase263_p0_pattern2_seg_min.hako: loop body で seg 代入
- tools/.../phase263_p0_pattern2_seg_vm.sh: VM smoke test
- 現状: Pattern2 rejection で FAIL（固定）
- 期待: 修正後に Pattern1 fallback で PASS

apps/tests/phase263_p0_pattern2_seg_min.hako

@@ -0,0 +1,35 @@
+// Phase 263 P0: Pattern2 LoopBodyLocal "seg" 問題の最小再現テスト
+//
+// 目的:
+// - loop body で代入される seg 変数を Pattern2 が promote しようとして失敗する
+// - 現状: Pattern2 rejection で FAIL
+// - 期待: 修正後に Pattern1 fallback で PASS
+
+static box Main {
+    main() {
+        local result = parse_segments()
+        return 0
+    }
+}
+
+// Pattern2 が検出するループ構造
+method parse_segments() {
+    local i = 0
+    local seg = ""
+
+    loop(i < 5) {
+        seg = get_segment(i)  // ← loop body で代入（ReadOnlySlot 契約違反）
+
+        if seg == "end" {
+            break
+        }
+
+        i = i + 1
+    }
+
+    return i
+}
+
+method get_segment(idx) {
+    return "seg"
+}

tools/smokes/v2/profiles/integration/apps/phase263_p0_pattern2_seg_vm.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "$SCRIPT_DIR/../../common.sh"
+
+APP_PATH="apps/tests/phase263_p0_pattern2_seg_min.hako"
+
+run_vm_test "$APP_PATH" "phase263_p0_pattern2_seg_min"