refactor(webui): isolate websocket application orchestration (#5548)

* refactor(webui): extract session attach projection

* refactor(webui): isolate websocket application orchestration

* refactor(webui): tighten websocket application boundary

* test(webui): assert module logger for fork failures

tests/webui/test_session_identity.py

@@ -0,0 +1,24 @@
+from nanobot.webui.session_identity import (
+    WEBUI_SESSION_STORAGE_PREFIX,
+    is_valid_webui_chat_id,
+    is_webui_session_key,
+    webui_chat_id,
+    webui_session_key,
+)
+
+
+def test_webui_session_identity_preserves_persisted_wire_compatibility() -> None:
+    assert WEBUI_SESSION_STORAGE_PREFIX == "websocket:"
+    assert webui_session_key("chat-1") == "websocket:chat-1"
+    assert is_webui_session_key("websocket:chat-1")
+    assert webui_chat_id("websocket:chat-1") == "chat-1"
+    assert webui_chat_id("websocket: chat-1") == " chat-1"
+    assert webui_chat_id("websocket:") is None
+    assert webui_chat_id("telegram:chat-1") is None
+
+
+def test_webui_chat_id_validation_is_protocol_scoped() -> None:
+    assert is_valid_webui_chat_id("unified:default")
+    assert is_valid_webui_chat_id("x" * 64)
+    assert not is_valid_webui_chat_id("x" * 65)
+    assert not is_valid_webui_chat_id("../escape")