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>

THIRD_PARTY_NOTICES.md

@@ -0,0 +1,15 @@
+# Third-party software
+
+This project is MIT-licensed (see `LICENSE`). `<project>` below is the CMake project name
+(`frameassistant`). Builds include or use:
+
+| Component | License | How it is used |
+|-----------|---------|----------------|
+| [OpenVR SDK](https://github.com/ValveSoftware/openvr) (`libopenvr_api.so`, `openvr.h`) | BSD-3-Clause | Shipped in `lib/`; license in `share/doc/<project>/third-party/openvr.LICENSE` |
+| [Qt 6](https://www.qt.io/) (Core, Gui, Qml, Quick, Quick Controls, Wayland/XCB plugins) | LGPL-3.0 (Qt open-source license) | Linked dynamically. Default builds use the system's Qt (not shipped). Bundled builds ship Qt's shared libraries unmodified in `lib/`, `plugins/`, `qml/`: replace them to use another compatible Qt build |
+
+**Bundled builds** (`--bundle-qt`) also ship further shared libraries that Qt depends on,
+taken unmodified from Debian. Their copyright and license files are in
+`share/doc/<project>/third-party/` (one `<package>.copyright` per Debian package, plus
+the license texts they reference). The corresponding sources are available from Debian
+(https://sources.debian.org/, package names as in those file names).