#118: the eject slot graphic lands -- BitMapInverseWipeScalar reconstructed

The operator's field report ("eject slot flashing but no graphic in it") was
the tracked-NULL bring-up stub in BallisticWeaponCluster. Reconstructed the
missing gauge class from the binary:

- BitMapInverseWipeScalar @004c61c8 (vtable 0x518a14; base @004c5e84,
  Execute @004c5fb8, BecameActive @004c5fa4): a bitmap COLUMN SWEEP whose
  level tracks a live Scalar -- two spans with INVERTED colour pairs,
  [0..level] fg colorA / bg colorB, remainder the inverse.
- Wired per the binary call site (part_014.c:2312): bteejtm.pcc at (0xF,0)
  on the weapon's eng port, colours 0/0xFF, watching the weapon's
  PercentOfEject (@0x3F8, the round-eject 0..1 progress) via a new
  complete-type bridge BTWeaponPercentOfEjectPtr (databinding rule).

At idle (level 0) the EJECT graphic now renders in the slot; during a
round-eject cycle it sweeps with the countdown. BTEEJTM.PCC ships in
content/GAUGE (the loose gauge bitmap set). Smoke-tested: constructs clean.

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

game/reconstructed/projweap.cpp

@@ -268,6 +268,17 @@ void *
 		? (void *)((ProjectileWeapon *)weapon)->ammoBinLink.Resolve() : 0;
 }
 
+// Eject-wipe gauge bridge (#118): the BallisticWeaponCluster's
+// BitMapInverseWipeScalar watches the weapon's PercentOfEject (@0x3F8, the
+// binary passes param_8+0x3f8 straight into the @004c61c8 ctor).  Complete-
+// type TU per the databinding rule -- never raw-offset a compiled object.
+Scalar *
+	BTWeaponPercentOfEjectPtr(void *weapon)
+{
+	return (weapon != 0)
+		? &((ProjectileWeapon *)weapon)->percentOfEject : 0;
+}
+
 
 //#############################################################################
 // Construction / Destruction