Docs: credit ported work and cover today's merged changes

Add CREDITS.md, listing the projects the fork is built on and every
change ported from upstream WiiCompiled and other forks, with author and
source commit, taken from the commit messages. Link it from the README,
THIRD-PARTY-NOTICES.md and a new porting note in CONTRIBUTING.md.

Document adaptive_resolution in OPENXR.md, the 4 KiB page constant and
NEON mixing in the README, the Mozilla CA bundle in the notices, and draft
the frame-beta-3 release notes for what PRs #5 to #10 merged.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Axv1Y43Lu5a5rSSLUyU5BB

THIRD-PARTY-NOTICES.md

@@ -88,6 +88,19 @@ wheel geometry and guest reads in `runtime/src/vr/mkw_vr_first_person.cpp` and
 (`runtime/include/physical_wheel.h`, `runtime/src/physical_wheel.cpp` and their test). The files
 carry that attribution in their headers.
 
+### Mozilla CA certificate bundle - MPL-2.0
+
+The root certificates Mbed TLS verifies servers against on Linux, macOS and Android
+(`runtime/assets/certs/cacert.pem`), copied next to the built game. Extracted from Mozilla's
+`certdata.txt` and redistributed unmodified as curl's CA bundle.
+Source: <https://curl.se/docs/caextract.html>
+
+### Code ported from other WiiCompiled forks - GPL-3.0-or-later
+
+Fixes taken from other GPL-3.0 forks of WiiCompiled (heurazy's Wiicompiled_VR-PLUS, KartPad,
+DarthMDev, Strikers-WiiCompiled, rooklz and wiicompiled-nx) are listed with their authors and
+source commits in [`CREDITS.md`](CREDITS.md).
+
 ### pugixml - MIT
 
 Copyright (c) 2006-2025 Arseny Kapoulkine.