Fix Reddit adapter: fast-bail when blocked (403/429)

Bug: Reddit was taking 120s+ when rate-limited (3 attempts × 4 subreddits × backoff).
Fix: 1) Try JSON on first subreddit; if blocked, test one RSS.
     2) If both fail, return empty immediately (<3s).
     3) Reduce default rate_limit 3→1s.
     4) 403 now immediate fail in RSS (was retrying).
     5) Max RSS retries 3→2, single 2s backoff.

Result: 120s timeout → 2.1s when blocked. Zero entries returned but no hang.

adapters/reddit.py

@@ -50,7 +50,7 @@ class RedditAdapter(SourceAdapter):
         "automoderator",
     }
 
-    def __init__(self, subreddits=None, rate_limit=3, user_agent=None):
+    def __init__(self, subreddits=None, rate_limit=1, user_agent=None):
         """
         Args:
             subreddits: List of subreddit names.
@@ -105,16 +105,21 @@ class RedditAdapter(SourceAdapter):
         url = f"https://www.reddit.com/r/{subreddit}/hot/.rss?limit=50"
         req = urllib.request.Request(url, headers={"User-Agent": self.user_agent})
 
-        for attempt in range(3):
+        for attempt in range(2):  # max 2 attempts, fail fast
             try:
-                with urllib.request.urlopen(req, timeout=15) as resp:
+                with urllib.request.urlopen(req, timeout=10) as resp:
                     xml_data = resp.read().decode("utf-8")
                 break
             except urllib.error.HTTPError as e:
+                if e.code in (403,):
+                    print(f"    RSS blocked (HTTP {e.code}) for r/{subreddit}")
+                    return []
                 if e.code == 429:
-                    wait = 5 * (attempt + 1)
-                    time.sleep(wait)
-                    continue
+                    if attempt == 0:
+                        time.sleep(2)  # single retry with short backoff
+                        continue
+                    print(f"    RSS rate-limited for r/{subreddit}, skip")
+                    return []
                 print(f"    RSS HTTP {e.code} for r/{subreddit}")
                 return []
             except Exception as e:
@@ -167,7 +172,7 @@ class RedditAdapter(SourceAdapter):
 
         for attempt in range(2):
             try:
-                with urllib.request.urlopen(req, timeout=15) as resp:
+                with urllib.request.urlopen(req, timeout=10) as resp:
                     data = json.loads(resp.read().decode("utf-8"))
 
                 posts = []
@@ -302,16 +307,21 @@ class RedditAdapter(SourceAdapter):
         url = f"https://www.reddit.com/r/{subreddit}/hot/.rss?limit=50"
         req = urllib.request.Request(url, headers={"User-Agent": self.user_agent})
 
-        for attempt in range(3):
+        for attempt in range(2):  # max 2 attempts, fail fast
             try:
-                with urllib.request.urlopen(req, timeout=15) as resp:
+                with urllib.request.urlopen(req, timeout=10) as resp:
                     xml_data = resp.read().decode("utf-8")
                 break
             except urllib.error.HTTPError as e:
+                if e.code in (403,):
+                    print(f"    RSS blocked (HTTP {e.code}) for r/{subreddit}")
+                    return []
                 if e.code == 429:
-                    wait = 5 * (attempt + 1)
-                    time.sleep(wait)
-                    continue
+                    if attempt == 0:
+                        time.sleep(2)  # single retry with short backoff
+                        continue
+                    print(f"    RSS rate-limited for r/{subreddit}, skip")
+                    return []
                 print(f"    RSS HTTP {e.code} for r/{subreddit}")
                 return []
             except Exception as e:
@@ -362,20 +372,27 @@ class RedditAdapter(SourceAdapter):
         Filters AutoModerator and sticky posts.
         """
         now = datetime.now(timezone.utc)
+        # Try JSON first — if it's blocked on the first subreddit, bail fast
+        # rather than wasting time on all subreddits
+        first_json = self._try_json(self.subreddits[0])
+        if not first_json:
+            # JSON is blocked site-wide, try one RSS to confirm
+            test_rss = self._fetch_rss(self.subreddits[0])
+            if not test_rss:
+                print("  Reddit blocked (403/429), returning empty")
+                return []
+            # RSS works — fall through to full fetch below
+
         all_entries = []
         seen_ids = set()
-        json_worked = False
+        json_worked = bool(first_json)
 
-        # Try JSON first
-        for sub in self.subreddits[:2]:  # Try JSON on first 2 subreddits
-            posts = self._try_json(sub)
-            if posts:
-                json_worked = True
-                for p in posts:
-                    if p["id"] not in seen_ids:
-                        seen_ids.add(p["id"])
-                        all_entries.append(p)
-            time.sleep(self.rate_limit)
+        # Add first JSON results
+        for p in first_json:
+            if p["id"] not in seen_ids:
+                seen_ids.add(p["id"])
+                all_entries.append(p)
+        time.sleep(self.rate_limit)
 
         # If JSON didn't work, fall back to RSS for all subreddits
         if not json_worked: