fix(dataflows): map crypto to StockTwits/Reddit sentiment symbols

- crypto reached StockTwits as Yahoo's BTC-USD (404) instead of BTC.X, and Reddit
  searched the dashed pair that barely matches; both now resolve the base via a
  shared crypto_base() helper, restoring crypto sentiment
- also fixes a StockTwits resilience test class that pytest never collected #1113

tradingagents/dataflows/reddit.py

@@ -30,6 +30,8 @@ from urllib.error import HTTPError
 from urllib.parse import urlencode
 from urllib.request import Request, urlopen
 
+from .symbol_utils import crypto_base
+
 logger = logging.getLogger(__name__)
 
 _API = "https://www.reddit.com/r/{sub}/search.json?{qs}"
@@ -200,6 +202,9 @@ def fetch_reddit_posts(
     stay under Reddit's public per-IP rate limit; combined with the RSS-first
     path it makes 429s rare even when several analyses run back-to-back.
     """
+    # Crypto reaches us as a Yahoo pair (BTC-USD); search Reddit for the base
+    # ("BTC") so the query actually matches discussion instead of near-nothing.
+    ticker = crypto_base(ticker) or ticker
     blocks = []
     total_posts = 0
     for i, sub in enumerate(subreddits):