feat：替换角色资源并增加基础tilesetlayer

- 增加底纹、草坪、河堤、河、小码头以及公会的tilesetlayer
- 替换角色精灵图为 4 行 4 列格式
- 更新 player.tscn：配置上下左右的 idle 和 walk 动画
- 更新 player.gd：重构动画逻辑，支持四方向判断与播放

project.godot

@@ -29,10 +29,10 @@ gdscript/warnings/treat_warnings_as_errors=false
 
 [display]
 
-window/size/viewport_width=1376
-window/size/viewport_height=768
+window/size/viewport_width=1920
+window/size/viewport_height=1440
 window/size/mode=2
-window/stretch/mode="canvas_items"
+window/stretch/mode="viewport"
 window/stretch/aspect="expand"
 
 [gui]
@@ -85,6 +85,8 @@ locale/test="zh_CN"
 renderer/rendering_method="gl_compatibility"
 renderer/rendering_method.mobile="gl_compatibility"
 textures/vram_compression/import_etc2_astc=true
+2d/snap/snap_2d_transforms_to_pixel=true
+2d/snap/snap_2d_vertices_to_pixel=true
 fonts/dynamic_fonts/use_oversampling=true
 debug/disable_vsync=false
 debug/settings/stdout/print_fps=false