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>

deploy/docker/truenas-compose.yml

@@ -77,6 +77,7 @@ x-app: &app
     TRADING_REGIME_GATE_P_MIN: '0.5'
     TRADING_EXIT_TRAIL_AFTER_R: '1.0'
     TRADING_EXIT_TRAIL_MODE: 'prior_low'
+    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_LIQUIDITY_MAX_VOLUME_PCT: '0.025'
     TRADING_MAX_BACKOUTS_PER_SYMBOL: '3'