feat: add multi-provider LLM support with thinking configurations

Models added:
- OpenAI: GPT-5.2, GPT-5.1, GPT-5, GPT-5 Mini, GPT-5 Nano, GPT-4.1
- Anthropic: Claude Opus 4.5/4.1, Claude Sonnet 4.5/4, Claude Haiku 4.5
- Google: Gemini 3 Pro/Flash, Gemini 2.5 Flash/Flash Lite
- xAI: Grok 4, Grok 4.1 Fast (Reasoning/Non-Reasoning)

Configs updated:
- Add unified thinking_level for Gemini (maps to thinking_level for Gemini 3,
  thinking_budget for Gemini 2.5; handles Pro's lack of "minimal" support)
- Add OpenAI reasoning_effort configuration
- Add NormalizedChatGoogleGenerativeAI for consistent response handling

Fixes:
- Fix Bull/Bear researcher display truncation
- Replace ChromaDB with BM25 for memory retrieval

tradingagents/default_config.py

@@ -3,16 +3,18 @@ import os
 DEFAULT_CONFIG = {
     "project_dir": os.path.abspath(os.path.join(os.path.dirname(__file__), ".")),
     "results_dir": os.getenv("TRADINGAGENTS_RESULTS_DIR", "./results"),
-    "data_dir": "/Users/yluo/Documents/Code/ScAI/FR1-data",
     "data_cache_dir": os.path.join(
         os.path.abspath(os.path.join(os.path.dirname(__file__), ".")),
         "dataflows/data_cache",
     ),
     # LLM settings
     "llm_provider": "openai",
-    "deep_think_llm": "o4-mini",
-    "quick_think_llm": "gpt-4o-mini",
+    "deep_think_llm": "gpt-5.2",
+    "quick_think_llm": "gpt-5-mini",
     "backend_url": "https://api.openai.com/v1",
+    # Provider-specific thinking configuration
+    "google_thinking_level": None,      # "high", "minimal", etc.
+    "openai_reasoning_effort": None,    # "medium", "high", "low"
     # Debate and discussion settings
     "max_debate_rounds": 1,
     "max_risk_discuss_rounds": 1,
@@ -20,14 +22,13 @@ DEFAULT_CONFIG = {
     # Data vendor configuration
     # Category-level configuration (default for all tools in category)
     "data_vendors": {
-        "core_stock_apis": "yfinance",       # Options: yfinance, alpha_vantage, local
-        "technical_indicators": "yfinance",  # Options: yfinance, alpha_vantage, local
-        "fundamental_data": "alpha_vantage", # Options: openai, alpha_vantage, local
-        "news_data": "alpha_vantage",        # Options: openai, alpha_vantage, google, local
+        "core_stock_apis": "yfinance",       # Options: yfinance, alpha_vantage
+        "technical_indicators": "yfinance",  # Options: yfinance, alpha_vantage
+        "fundamental_data": "alpha_vantage", # Options: alpha_vantage, yfinance
+        "news_data": "yfinance",             # Options: yfinance, alpha_vantage
     },
     # Tool-level configuration (takes precedence over category-level)
     "tool_vendors": {
         # Example: "get_stock_data": "alpha_vantage",  # Override category default
-        # Example: "get_news": "openai",               # Override category default
     },
 }