Reconstruct readable C++ and organize cohesive source subsystems

Administrative source import: native x86 compilation passed for 423 authored units. Source placement and submission states are migrated separately; this commit does not imply peer acceptance.

Previous head: 35d2a8cb36
Payload SHA256: 592f016d2730c5593bb653aa054c1e5f76a6df72c8f5a09e66f74876e2e33dee

Source/Client/Input/InputCharset.cpp

@@ -0,0 +1,24 @@
+#include "Client/Input/InputCharset.h"
+#include "Utility/Text/LanguageCharset.h"
+
+#include <cstdio>
+
+// OFFSET: 0x00ACE360
+// FUNCTION: fn_17781
+const char* InputCharset::Prefix(bool alternate) const {
+  // STATIC: 0x016D3964
+  // GLOBAL: gl_24373
+  static char prefix[8];
+
+  if (this->enabled) {
+    std::sprintf(prefix, "|%02x", LanguageCharset(alternate ? this->alternateLanguage : this->language));
+  } else {
+    prefix[0] = '\0';
+  }
+
+  return prefix;
+}
+
+unsigned InputCharset::CodePage(unsigned fallback) const {
+  return this->enabled ? LanguageCodePage(this->language) : fallback;
+}