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

systems/fx/blood_burst.gd

@@ -0,0 +1,49 @@
+extends CPUParticles3D
+## One-shot blood spray. Add as a child of whatever bleeds, then call burst().
+
+func _ready() -> void:
+	var mat := StandardMaterial3D.new()
+	mat.shading_mode = BaseMaterial3D.SHADING_MODE_UNSHADED
+	mat.transparency = BaseMaterial3D.TRANSPARENCY_ALPHA
+	mat.vertex_color_use_as_albedo = true
+	mat.cull_mode = BaseMaterial3D.CULL_DISABLED
+
+	var sphere := SphereMesh.new()
+	sphere.radius = 0.07
+	sphere.height = 0.14
+	sphere.radial_segments = 4
+	sphere.rings = 2
+	sphere.material = mat
+
+	var ramp := Gradient.new()
+	ramp.set_color(0, Color(1.0, 0.02, 0.02, 1.0))
+	ramp.set_color(1, Color(0.25, 0.0, 0.0, 0.0))
+
+	var scale_curve := Curve.new()
+	scale_curve.add_point(Vector2(0.0, 1.0))
+	scale_curve.add_point(Vector2(0.6, 0.5))
+	scale_curve.add_point(Vector2(1.0, 0.0))
+
+	mesh               = sphere
+	color_ramp         = ramp
+	scale_amount_curve = scale_curve
+	one_shot           = true
+	explosiveness      = 0.9
+	amount             = 25
+	lifetime           = 1.1
+	randomness         = 0.4
+	local_coords       = false
+	spread             = 80.0
+	gravity            = Vector3(0.0, -7.0, 0.0)
+	initial_velocity_min = 4.0
+	initial_velocity_max = 11.0
+	scale_amount_min   = 0.5
+	scale_amount_max   = 1.6
+	emitting           = false
+
+
+# Fire a burst at a world position, sprayed along dir (biased upward).
+func burst(at: Vector3, dir: Vector3) -> void:
+	global_position = at
+	direction = (dir * 0.6 + Vector3.UP * 0.4).normalized()
+	restart()