fix(tui): establish 2-tier readiness model, modal/hint token separation, and adapter modal contracts

- Separate TUI dialog detection into blocking gate layer (_MAM_MODAL_TOKENS) and recovery layer (_MAM_HINT_TOKENS) to eliminate idle dialog starvation
- Add modal_tokens contract across agent adapters (claude, cline) with dynamic scope facts resolution in send_keys_safe
- Implement fail-closed resolution for ambiguous same-kind panes (R-1) and enforce WORKSPACE_ROOT export (R-2)
- Preserve session on TUI readiness timeout when PID is alive for diagnostics
- Add comprehensive test suite in tests/test_c1_tui_readiness.py and adapter contract assertions in test_a4

tests/test_b19_headless_reconcile_fixes.py

@@ -284,8 +284,10 @@ if _pane_dialog_open dummy; then echo "DIALOG_OPEN"; else echo "DIALOG_CLOSED";
 def test_mam_dialog_tokens_exclude_yes_try_it():
     """N-1 / F-1: token list must not contain Yes, try it; Escape branch stays."""
     content = open(_LIB_SH, encoding="utf-8").read()
-    token_line = next(l for l in content.splitlines() if l.startswith("_MAM_DIALOG_TOKENS="))
-    assert "Yes, try it" not in token_line
+    modal_line = next(l for l in content.splitlines() if l.startswith("_MAM_MODAL_TOKENS="))
+    hint_line = next(l for l in content.splitlines() if l.startswith("_MAM_HINT_TOKENS="))
+    assert "Yes, try it" not in modal_line
+    assert "Yes, try it" not in hint_line
     assert "grep -q 'Yes, try it'" in content