Per-pilot mech paint: wire the color/badge/patch substitution end-to-end

- Mech::resourceNameA/B/C -> real CString members (the binary's 16-byte
  CStringRepresentation; deep-copy bind from the MakeMessage = FUN_00402a98,
  implicit member dtors) + paint-name accessors
- SetupMaterialSubstitutionList reads the real egg names ([paint] log);
  TearDown clears the callback first (FUN_004d11e8)
- dpl_SetMaterialNameCallback is real now (L4VIDEO registry); bgfload
  MaterialResolver::resolve() applies it to every material name -- the
  port analogue of the dpl board rewriting names at load
- MP_BHMC.EGG: color=Red -> Crimson (vehicletable has no Red; binary Fail()ed)

Verified live 2-node MP: crimson MadCat with hip hazard stripes + yellow VGL
leg emblems; white Blackhawk + emblems; replicants painted on both nodes.

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

engine/MUNGA_L4/bgfload.cpp

@@ -11,6 +11,11 @@
 #include <set>
 #include <array>
 
+// L4VIDEO.cpp: the dpl material-name callback registry.  While a mech loads
+// (the SetupMaterialSubstitutionList / TearDown bracket) this rewrites
+// "blhskin:..." -> "blh_wht0:..." / "emblem0:..." -- the per-pilot paint.
+std::string dpl_ApplyMaterialNameCallback(const std::string &name);
+
 namespace {
 
 // ---- DIV-BIZ2 tag ids (PFBIZTAG.H), masked form (tagword & 0x2fff) ----
@@ -503,7 +508,11 @@ struct MaterialResolver {
         return libs.emplace(lib, std::move(table)).first->second;
     }
 
-    MatInfo resolve(const std::string& full) {
+    MatInfo resolve(const std::string& fullIn) {
+        // Per-pilot paint: run the name through the installed dpl material-name
+        // callback first (identity when none) -- the board rewrote names at
+        // load time, before any material lookup.
+        std::string full = dpl_ApplyMaterialNameCallback(fullIn);
         auto cached = resolvedCache.find(full);
         if (cached != resolvedCache.end()) return cached->second;
         MatInfo info;