feat: productionize local service — fix signal pipeline, lower thresholds, add company-name ticker extraction

- Point Ollama to local instance via host.docker.internal, use gemma3 model
- Remove Docker Ollama service (using host's Ollama instead)
- Add company-name-to-ticker mapping (Apple→AAPL, Tesla→TSLA, etc.) for RSS articles
- Lower signal thresholds for faster feedback with paper trading:
  - FinBERT confidence: 0.6→0.4, signal strength: 0.3→0.15
  - News strategy: article_count 2→1, confidence 0.5→0.3, score ±0.3→±0.15
- Fix market data BarSet access bug (BarSet.__contains__ returns False incorrectly)
- Fix market data SIP feed error by switching to IEX feed for free Alpaca accounts
- Fix nginx proxy routing for /api/auth/* to api-gateway /auth/*
- Add seed_sample_data script
- Update tests for new thresholds and alpaca mock modules

services/api_gateway/auth/routes.py

@@ -167,9 +167,12 @@ async def register_complete(
     user_id_str = stored["user_id"]
     display_name = stored["display_name"]
 
+    # The frontend sends the WebAuthn response under "attestation" or "credential"
+    credential_data = body.get("credential") or body.get("attestation") or body
+
     try:
         verification = verify_registration_response(
-            credential=body.get("credential", body),
+            credential=credential_data,
             expected_challenge=expected_challenge,
             expected_rp_id=config.rp_id,
             expected_origin=config.rp_origin,
@@ -319,11 +322,14 @@ async def login_complete(
     expected_challenge = base64.urlsafe_b64decode(stored["challenge"])
     user_id_str = stored["user_id"]
 
+    # The frontend sends the WebAuthn response under "assertion" or "credential"
+    credential_data = body.get("credential") or body.get("assertion") or body
+
     # Look up the credential used
     from sqlalchemy import select
     from shared.models.auth import UserCredential
 
-    credential_id_b64 = body.get("credential", body).get("id", "")
+    credential_id_b64 = credential_data.get("id", "")
     db_session = request.app.state.db_session_factory
 
     async with db_session() as session:
@@ -343,7 +349,7 @@ async def login_complete(
 
         try:
             verification = verify_authentication_response(
-                credential=body.get("credential", body),
+                credential=credential_data,
                 expected_challenge=expected_challenge,
                 expected_rp_id=config.rp_id,
                 expected_origin=config.rp_origin,