fix(news): remove paid-tier 'from' param, add User-Agent, log status+body on error

- Drop the 'from' date filter — it's a paid GNews feature, causes 403 on free tier
- Add User-Agent header to httpx client; urllib default passes, httpx default blocked
- Log actual HTTP status code for every request (INFO) and response body on non-200
- Cache neutral result on 400/401/403/429 to avoid hammering the quota
- Remove unused _iso_days_ago() helper and 'days' param from get_sentiment()

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bot/data/news.py

@@ -12,7 +12,6 @@ import logging
 import os
 import re
 import time
-from datetime import datetime, timezone, timedelta
 
 import httpx
 
@@ -76,7 +75,10 @@ class NewsClient:
 
     def __init__(self) -> None:
         self._api_key = os.getenv("GNEWS_API_KEY", "")
-        self._client = httpx.AsyncClient(timeout=10)
+        self._client = httpx.AsyncClient(
+            timeout=10,
+            headers={"User-Agent": "Mozilla/5.0 (compatible; polymarket-bot/1.0)"},
+        )
         # {cache_key: (fetched_at_monotonic, score)}
         self._cache: dict[str, tuple[float, float]] = {}
 
@@ -84,7 +86,7 @@ class NewsClient:
     # Public API
     # ------------------------------------------------------------------
 
-    async def get_sentiment(self, question: str, days: int = 7) -> float:
+    async def get_sentiment(self, question: str) -> float:
         """
         Return a sentiment score ∈ [-1.0, +1.0] for the market question.
 
@@ -109,6 +111,9 @@ class NewsClient:
                 log.debug("News cache hit %r → %.3f", query, score)
                 return score
 
+        # Build URL exactly as documented for free tier:
+        # https://gnews.io/api/v4/search?q=...&lang=en&max=10&token=...
+        # NOTE: "from"/"to" date filters are paid-tier only — omit them.
         try:
             resp = await self._client.get(
                 GNEWS_API,
@@ -116,7 +121,6 @@ class NewsClient:
                     "q": query,
                     "lang": "en",
                     "max": 10,
-                    "from": _iso_days_ago(days),
                     "token": self._api_key,
                 },
             )
@@ -124,17 +128,23 @@ class NewsClient:
             log.warning("GNews network error for %r: %s", query, exc)
             return 0.0
 
-        if resp.status_code == 403:
-            log.warning("GNews: 403 — invalid key or daily quota exhausted")
-            # Cache a neutral result for 1 h to avoid hammering the endpoint
-            self._cache[cache_key] = (now, 0.0)
+        log.info("GNews HTTP %d for query %r", resp.status_code, query)
+
+        if resp.status_code != 200:
+            try:
+                body = resp.json()
+            except Exception:
+                body = resp.text[:200]
+            log.warning("GNews error body: %s", body)
+            # Cache neutral for 1 h on client errors to avoid hammering the endpoint
+            if resp.status_code in (400, 401, 403, 429):
+                self._cache[cache_key] = (now, 0.0)
             return 0.0
 
         try:
-            resp.raise_for_status()
             data = resp.json()
         except Exception as exc:
-            log.warning("GNews bad response for %r: %s", query, exc)
+            log.warning("GNews JSON decode error for %r: %s", query, exc)
             return 0.0
 
         articles = data.get("articles", [])
@@ -186,8 +196,3 @@ class NewsClient:
             votes.append((pos - neg) / total if total > 0 else 0.0)
 
         return max(-1.0, min(1.0, sum(votes) / len(votes)))
-
-
-def _iso_days_ago(days: int) -> str:
-    dt = datetime.now(timezone.utc) - timedelta(days=days)
-    return dt.strftime("%Y-%m-%dT%H:%M:%SZ")