fix #266: retail run-rate 800 branch is exact-equality sentinel, not a cap

Raw byte decode of MovementSystem::GetRunRate (0x006b0950, PDB-paired
binary): fild skill; fcom [800f]; fnstsw; test ah, 0x44; jp general —
the C2/C3 parity idiom whose 18/4 fall-through executes ONLY at
skill == 800 exactly. ACE read this as >= 800 ('max run speed?') and
Campaign P P1 inherited that misread when BN dropped the arithmetic,
flat-lining every maxed character at 4.5 (retail-true ~3.70, +21%) and
erasing the vitae differential (both 10200 and 15225 sat above 800).

The [stat-chain] live capture proved the enchant chain correct end to
end (vitae 0.67 -> eff run 10200 -> controller), isolating the formula.
General path byte-verified: (loadMod*(skill/(skill+200)*11)+4)/scaling/4.
InqMaxRunRate's skill=9999 probe gets ~3.6961, not 4.5.

Golden tests pin the 799/800/801 straddle and the maxed-skill vitae
differential; pseudocode doc §6 carries the decode plus a do-not-
reimport-ACE warning. Complete Release suite: 10,025 passed / 5 skips.

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

src/AcDream.Core/Physics/PlayerWeenie.cs

@@ -200,7 +200,8 @@ public sealed class PlayerWeenie : IWeenieObject
 
     /// <summary>
     /// RunRate = (burdenMod * (runSkill / (runSkill + 200)) * 11 + 4) / 4.
-    /// Capped at 4.5 when runSkill >= 800. Thin forwarder to
+    /// Returns 4.5 only for the retail skill == 800 sentinel (byte-decoded
+    /// exact-equality branch, #266 — NOT a cap). Thin forwarder to
     /// <see cref="MovementSystem.GetRunRate"/> — kept for source
     /// compatibility with existing golden-value tests.
     /// </summary>