fix(odds): don't return the cached no-odds marker as odds (#662)

A game ESPN had no odds for is cached as {"no_odds": True}, so it isn't
re-requested on every update. On the next update get_odds() returned that
marker from the cache as if it were odds: a truthy dict that callers took
to mean the game had some. It's still a cache hit (its ttl decides when to
ask again), but get_odds() now returns None for it -- on the cache hit and
in the stale-cache fallback after a failed fetch -- as the plugins' bundled
copies already did.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

src/base_odds_manager.py

@@ -21,6 +21,11 @@ from typing import Dict, Any, Optional, List
 from src.common.api_helper import DEFAULT_HTTP_HEADERS
 
 
+
+def _is_no_odds_marker(data: Any) -> bool:
+    """Whether a cached odds entry is the "ESPN had none" marker, not odds."""
+    return isinstance(data, dict) and bool(data.get("no_odds"))
+
 class BaseOddsManager:
     """
     Base class for odds data fetching and management.
@@ -126,6 +131,14 @@ class BaseOddsManager:
         # Per-game chatter, logged on every update of every game on the
         # slate: debug, not the journal.
         if cached_data:
+            # A game ESPN had no odds for is cached as {"no_odds": True} so it
+            # isn't re-requested every update. That marker is a cache hit --
+            # its ttl decides when to ask again -- but it is not odds: returned
+            # as-is, a caller saw a truthy dict and treated the game as having
+            # odds. The plugins' bundled copies already did this.
+            if _is_no_odds_marker(cached_data):
+                self.logger.debug("Cached no-odds marker for %s", cache_key)
+                return None
             self.logger.debug(f"Using cached odds from ESPN for {cache_key}")
             return cached_data
 
@@ -189,8 +202,9 @@ class BaseOddsManager:
                 "Error fetching odds from ESPN API for %s: %s. Holding off on odds "
                 "for %.0fs so a slate of games does not pay this timeout each.",
                 cache_key, e, self._FAILURE_COOLDOWN)
-        
-        return self.cache_manager.get_with_auto_strategy(cache_key)
+
+        cached = self.cache_manager.get_with_auto_strategy(cache_key)
+        return None if _is_no_odds_marker(cached) else cached
 
     def _extract_espn_data(self, data: Dict[str, Any]) -> Optional[Dict[str, Any]]:
         """