feat(bot): dialog engine — scrub → safety → FSM → monitoring, consent, age gate, crisis

- Engine.handle registered via register_engine; lexicon-first safety (no LLM on ACUTE),
  fixed crisis script once per open crisis, POSSIBLE → C-SSRS screen
- FSM registry (@state/@on_enter/@trigger) with auto-loaded flows; core flow:
  new → consent → age_gate → module onboarding → idle, crisis, consent_revoked
- reusable scale session (buttons, extract_item + clarify, item 9 / C-SSRS buttons-only,
  crisis flags), execution of monitoring dialog actions, texts in config/texts/dialog.yaml

Refs #10

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/dialog/flows/__init__.py

@@ -0,0 +1,16 @@
+"""Dialog flows. Each module here registers its FSM states at import time (`@state`, `@on_enter`, `@trigger`).
+
+A new direction (veteran #36/#37, family, depression) is a new file `app/dialog/flows/<module>.py`; it is picked
+up automatically by `load_flows()` — the engine is not edited.
+"""
+
+import pkgutil
+from importlib import import_module
+
+
+def load_flows() -> None:
+    """Import every flow module of this package (core first, so flows may override core triggers)."""
+    import_module(f"{__name__}.core")
+    for info in sorted(pkgutil.iter_modules(__path__), key=lambda m: m.name):
+        if info.name != "core" and not info.name.startswith("_"):
+            import_module(f"{__name__}.{info.name}")