feat(ModularBot): pluggable bot with 4 guns, phantom meteor movement, radar harness

- Gun harness: virtual bullet tracker, rolling fitness, auto-selector
- Guns: head-on, linear (extrapolation), circular (integrated formula), tsetlin machine (learning)
- Movement: phantom meteor gravity engine (danger histograms, phantom bullets, fire detection)
- Radar: harness + radar_lock adapter
- Color-coded modules: turret/bullet color per gun, body per movement, scan per radar
- Beats Target, SpinBot, Crazy, TrackFire in 10-round battles

common_libs/radars/radar_lock_module.nim

@@ -0,0 +1,18 @@
+## RadarLock adapter — wraps radar_lock.doRadar() as a RadarModule.
+
+import std/math
+import ../radar_harness/radar_interface
+import ../radar_lock/radar_lock as radar_lock_impl
+
+export radar_interface
+
+type RadarLockModule* = object
+
+proc computeScan*(m: RadarLockModule, state: WorldState): float =
+  ## Returns radar turn rate (deg/tick) to lock onto enemy.
+  let enemyBearing = arctan2(state.enemyY - state.selfY,
+                              state.enemyX - state.selfX).radToDeg
+  radar_lock_impl.doRadar(state.selfRadarHeading, enemyBearing)
+
+proc init*(m: var RadarLockModule) =
+  radar_lock_impl.init()