Initial FrameAssistant baseline from the vrdashboard template

Template stripped to the overlay platform (examples, demo UI and Frame
test package removed), renamed to FrameAssistant, and working rules for
the project recorded in CLAUDE.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/AppConfig.h.in

@@ -0,0 +1,15 @@
+#pragma once
+
+// Generated by CMake from src/AppConfig.h.in — edit the cache variables in
+// CMakeLists.txt.
+
+namespace AppConfig {
+inline constexpr char kAppKey[] = "@VRDASH_APP_KEY@";
+inline constexpr char kDisplayName[] = "@VRDASH_DISPLAY_NAME@";
+inline constexpr char kVersion[] = "@PROJECT_VERSION@";
+inline constexpr int kTextureWidth = @VRDASH_TEXTURE_WIDTH@;
+inline constexpr int kTextureHeight = @VRDASH_TEXTURE_HEIGHT@;
+// Resource directory relative to the executable (same in build and install
+// tree).
+inline constexpr char kShareDirFromBin[] = "../@VRDASH_SHARE_SUBDIR@";
+} // namespace AppConfig