fix(odds): identify the odds requests to ESPN (#451)

The odds fetch used a bare requests.get, so it went out as
python-requests/x.y -- the one agent ESPN is known to reject. Around
2026-08-04 it began 403ing browser strings and bare custom tokens alike;
what it accepts is a token carrying a URL that says who is calling.
Every other ESPN caller in the tree already sends that header
(src/common/api_helper.py, src/base_classes/data_sources.py); this path
was simply missed.

It is the worst one to miss. Odds are fetched per live game from inside
the live update loop, so its failures are the ones that cost the caller
its whole update budget -- the same path the 5s timeout and the cooldown
were added to protect.

Sent via a session rather than per-call, which also reuses the
connection across a slate. Deliberately no retry adapter, unlike
api_helper: retries multiply request_timeout, which is 5s precisely to
stay inside the 30s operation budget.

The existing tests patched the module's requests.get, which this change
bypasses -- test_base_odds_manager was consequently reaching the real
ESPN and taking 404s. Both files now patch the session, and the new
tests pin the agent against api_helper's live value so the two cannot
drift apart the next time ESPN moves the goalposts.


Claude-Session: https://claude.ai/code/session_01Udr6MfaFLUPhX5Fgo67Jf5

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>

src/base_odds_manager.py

@@ -44,6 +44,24 @@ class BaseOddsManager:
         self.config_manager = config_manager
         self.logger = logging.getLogger(__name__)
         self.base_url = "https://sports.core.api.espn.com/v2/sports"
+
+        # This path used a bare requests.get, so it identified itself as
+        # python-requests/x.y -- the one thing ESPN is known to reject. Around
+        # 2026-08-04 it began 403ing browser strings and bare custom tokens
+        # alike; what it accepts is a token with a URL that says who is
+        # calling. Every other ESPN caller in the tree already sends this
+        # (src/common/api_helper.py, src/base_classes/data_sources.py); the
+        # odds path was simply missed, and it is the one whose failures cost
+        # the caller its whole update budget.
+        #
+        # Deliberately no retry adapter, unlike api_helper: retries multiply
+        # request_timeout, which is set to 5s precisely to stay inside that
+        # budget. One try, then the cooldown below.
+        self.session = requests.Session()
+        self.session.headers.update({
+            'User-Agent': 'LEDMatrix/1.0 (+https://github.com/ChuckBuilds/LEDMatrix)',
+            'Accept': 'application/json',
+        })
         
         # Configuration with defaults
         self.update_interval = 3600  # 1 hour default
@@ -144,7 +162,7 @@ class BaseOddsManager:
             url = f"{self.base_url}/{sport}/leagues/{espn_league}/events/{event_id}/competitions/{event_id}/odds"
             self.logger.info(f"Requesting odds from URL: {url}")
             
-            response = requests.get(url, timeout=self.request_timeout)
+            response = self.session.get(url, timeout=self.request_timeout)
             response.raise_for_status()
             raw_data = response.json()