Reorganize the codebase into role-based folders (snake_case)

Move the 40-odd root-level scripts and scenes into a tree that groups by role,
per the approved roadmap (WS2/WS3): actors/{player,matador,bear}, systems/{combat,
fx,input,debug,render,crowd,config}, ui/, props/ (was tscn_s/). Rename the shell
scene.tscn -> levels/game_shell.tscn and every PascalCase scene to snake_case
(Player.tscn -> player.tscn, MainMenu.tscn -> main_menu.tscn, etc.) so the
case-insensitive web/macOS filesystems can't alias two files together.

Done as a scripted move: each file travels with its .uid; every quoted res:// path
across scenes, scripts, .tres, and project.godot's 9 autoloads is rewritten; the
.godot uid/class cache is rebuilt from scratch. Scenes still resolve by uid, so the
rewrite is belt-and-suspenders. Lint globs (run_tests.sh + both CI workflows) now
walk the new dirs; an orphan animation_tree.gd.uid and 7 pre-existing trailing-
whitespace lints (barrel/torch, never covered by the old root-only glob) are cleaned.

Full suite green on both sides. Asset consolidation (Assets/Animations/fonts ->
art/) is deferred — moving imported .glb/.png/.ttf is safer done in the editor.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017KoYBYQgRyY1zDHXMsXY3V

levels/lobby_level.tscn

@@ -1,7 +1,7 @@
 [gd_scene format=3 uid="uid://32nyipcwrab5"]
 
-[ext_resource type="PackedScene" uid="uid://bbfvwolhomilp" path="res://tscn_s/torch.tscn" id="1_w7uyf"]
-[ext_resource type="PackedScene" uid="uid://bd56iuttyiypv" path="res://tscn_s/BarrelSimple.tscn" id="2_3o0md"]
+[ext_resource type="PackedScene" uid="uid://bbfvwolhomilp" path="res://props/torch.tscn" id="1_w7uyf"]
+[ext_resource type="PackedScene" uid="uid://bd56iuttyiypv" path="res://props/barrel_simple.tscn" id="2_3o0md"]
 [ext_resource type="PackedScene" uid="uid://dctmlh4hnuux1" path="res://Assets/Lobby_underground.glb" id="2_w7uyf"]
 [ext_resource type="Script" uid="uid://cwbf7jfkr8j10" path="res://Assets/lobby_underground.gd" id="4_73452"]
 [ext_resource type="Script" uid="uid://dn77mjyxllgl6" path="res://levels/to_the_bear_level.gd" id="5_6j2sa"]