exits: manage every 4s not 12s — kill the give-back on fast small-cap round-trips

Owner's real complaint: late exits gave back gains. Exits ran on the slow
scheduler at 12s while entries run on the 4s fast thread — exits were 3x
slower than entries. A small-cap can spike and round-trip inside 12s. Drop
TRADING_EXIT_MANAGE_INTERVAL_SECONDS to 4s (config, reversible, both compose
files). Deeper fix (exit mgmt on the sub-second trigger thread) planned
separately. Entry chase-tail (24% fill >5% above break) is the next
investigation.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docker-compose.yml

@@ -45,6 +45,7 @@ x-app-env: &app-env
   # inherit them harmlessly.
   TRADING_EXIT_TRAIL_MODE: "prior_low"
   TRADING_EXIT_TRAIL_AFTER_R: "1.0"
+  TRADING_EXIT_MANAGE_INTERVAL_SECONDS: '4'  # 12->4s: react to fast small-cap round-trips (was giving back gains)
   TRADING_EXIT_TRAIL_R_STEP: "0.25"
   TRADING_EXIT_BREAKEVEN_R: "1.0"
   TRADING_EXIT_PROFIT_TIERS: "8:3,15:9,25:18,40:30"