fix(graph): integrate #487 + #567 — sentiment label, route, propagate asset_type

- analyst_execution.py: rename "Social Analyst" / "Msg Clear Social"
  to "Sentiment Analyst" / "Msg Clear Sentiment" to match v0.2.5.
- conditional_logic.should_continue_social returns the renamed route.
- TradingAgentsGraph.propagate accepts asset_type and threads through
  to Propagator.create_initial_state.
- Regression test on the Sentiment Analyst label.

Verified end-to-end (NVDA stock + BTC-USD crypto) on gpt-5.4-mini.

tradingagents/graph/analyst_execution.py

@@ -27,9 +27,13 @@ ANALYST_NODE_SPECS: Dict[str, AnalystNodeSpec] = {
         report_key="market_report",
     ),
     "social": AnalystNodeSpec(
+        # Wire key stays "social" for saved-config back-compat; the
+        # user-facing label is "Sentiment Analyst" to match the rename
+        # that landed in v0.2.5 (sentiment_analyst now ingests news +
+        # StockTwits + Reddit, not just social media).
         key="social",
-        agent_node="Social Analyst",
-        clear_node="Msg Clear Social",
+        agent_node="Sentiment Analyst",
+        clear_node="Msg Clear Sentiment",
         tool_node="tools_social",
         report_key="sentiment_report",
     ),