j145 TFIL: a turn-cost tiebreak among the SAFE tiles (default-off)

The picker scored candidates on pathMaxHeat alone and then drew uniformly
among the survivors, so a mirror-side tile was as likely as a straight-ahead
one. Added a continuous turn cost as a DRAW WEIGHT applied only after the
hard heat filter:

  w = max(1, round(1 + TR_TFIL_TURN_BIAS * (1 - max(0,|turn| - REF)/180)))

- TR_TFIL_TURN_BIAS (default 0) is the odds ratio straight-ahead vs 180 deg;
  TR_TFIL_TURN_REF_DEG (default 45) is where the penalty starts. Both
  default-off-effect: the default-path golden in test_tfil_commit_env.nim is
  unchanged and still passes.
- Turn cost is NEVER folded into the heat score. The filter stays hard.
- The draw stays random (j51 measured an argmin worse); every weight is
  floored at 1, so the pool can never be emptied and bias 0 is exactly the
  shipped uniform draw.
- |turn| now travels on the ScoredTile, and the commit log gained turn /
  minturn / promote so a caller can measure the regret of the draw.

Guards: 51 -> 66 checks (an absurd 99:1 bias never rescues an over-threshold
tile; mean |turn|, draw regret, >90 and mirror-side shares all fall; path
heat does not rise). env_report + .env.example updated.

ModularBot_garage/src/env_report.nim

@@ -324,6 +324,8 @@ proc printEffectiveValues(ctx: EnvReportContext) =
   emit("TR_TFIL_COMMIT_MARGIN", $TfilCommitMargin,
        sourceOf("TR_TFIL_COMMIT_MARGIN"))
   emit("TR_TFIL_NOREV_SPEED", $TfilNoRevSpeed, sourceOf("TR_TFIL_NOREV_SPEED"))
+  emit("TR_TFIL_TURN_BIAS", $TfilTurnBias, sourceOf("TR_TFIL_TURN_BIAS"))
+  emit("TR_TFIL_TURN_REF_DEG", $TfilTurnRefDeg, sourceOf("TR_TFIL_TURN_REF_DEG"))
   # time-indexed bullet heat (default off = shipped flat model)
   emit("TR_TFIL_HEAT_TIME", onOff(TfilHeatTime), sourceOf("TR_TFIL_HEAT_TIME"))
   emit("TR_TFIL_HEAT_TAU", $TfilHeatTau, sourceOf("TR_TFIL_HEAT_TAU"))
@@ -639,7 +641,7 @@ proc knownEnvNames*(): seq[string] =
     "TR_TFIL_WALL_RADIANCE",
     "TR_TFIL_TILE_REPLAN", "TR_TFIL_COMMIT_TICKS", "TR_TFIL_NO_REV",
     "TR_TFIL_COMMIT_LOG", "TR_TFIL_COMMIT_ARRIVAL", "TR_TFIL_COMMIT_MARGIN",
-    "TR_TFIL_NOREV_SPEED",
+    "TR_TFIL_NOREV_SPEED", "TR_TFIL_TURN_BIAS", "TR_TFIL_TURN_REF_DEG",
     "TR_TFIL_HEAT_TIME", "TR_TFIL_HEAT_TAU", "TR_TFIL_HEAT_POWER_GAIN",
     "TR_TFIL_PILLAR_ON",
     "TR_STRAFE_BAND", "TR_STRAFE_SPREAD", "TR_STRAFE_REACH",