chore(controller): three-player-controller als Ordner statt Submodul

Das Submodul zeigte auf GitHub, der eingetragene Stand 028c652 lag aber nur
lokal vor: GitHub-Master ac39682 plus Showcase mit Figuren und launch.json.
Frische Klone konnten den Controller deshalb nicht laden. Jetzt liegt dieser
Stand als normaler Ordner im Repo, ohne Verweis auf GitHub.

dist/ und node_modules/ im Controller bleiben ignoriert und werden wie bisher
lokal gebaut.

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

three-player-controller/LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 屈航
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.