KOL feeds: fix dead/blocked sources, drop stale feeds (29→25)

Feed-health pass over KOL_FEEDS:
- raoulpal: stale Substack (last 2024-05) → Real Vision podcast feed
- dampedspring: paywalled (0 entries) → free "Damped Spring 101" Substack
- unchained: Cloudflare 403 → canonical Megaphone podcast feed
- lynalden: Cloudflare 202 → FeedBurner mirror
- glassnode: recovered via httpx http2=True (was 403 on HTTP/1.1)
- browser User-Agent + Accept headers on feed fetch
- removed dead feeds with no active replacement: placeholder,
  dragonfly, niccarter, eugene
- pin h2==4.3.0 (required by http2=True)

All 25 remaining feeds verified fetching real body content; newest
post per feed ≤88d. Bundles in-flight KOL-module work already in the
working tree (kol_x ingest, migration 027, tests).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

app/services/hyperliquid.py

@@ -185,7 +185,12 @@ class HyperliquidTrader:
             )
             logger.info("Set leverage %dx for %s (isolated)", effective, coin)
         except Exception as exc:
-            logger.warning("set_leverage error (non-fatal): %s", exc)
+            # DO NOT swallow — if leverage isn't set, the position would open
+            # at whatever HL had previously. Downstream stop math
+            # (sys2_protective_stop_pct) uses the return value; a wrong
+            # value puts the stop outside the real liquidation line.
+            logger.error("set_leverage FAILED for %s %dx: %s — aborting open", coin, effective, exc)
+            raise RuntimeError(f"set_leverage failed for {coin} at {effective}×: {exc}") from exc
         return effective
 
     async def open_position(