Add new styleboxes and import energy texture

- Created a new SVG import for the energy texture, enabling better resource management and compression.
- Added a StyleBoxFlat resource for the top left panel with specified margins, background color, border width, and corner radius.
- Introduced a StyleBoxFlat resource for the top panel with similar properties, ensuring consistent UI design across panels.

resources/items/energy.svg.import

@@ -0,0 +1,37 @@
+[remap]
+
+importer="texture"
+type="CompressedTexture2D"
+uid="uid://k13cte17httt"
+path="res://.godot/imported/energy.svg-32660de09c2a807af89f2e5b1c1b0125.ctex"
+metadata={
+"vram_texture": false
+}
+
+[deps]
+
+source_file="res://resources/items/energy.svg"
+dest_files=["res://.godot/imported/energy.svg-32660de09c2a807af89f2e5b1c1b0125.ctex"]
+
+[params]
+
+compress/mode=0
+compress/high_quality=false
+compress/lossy_quality=0.7
+compress/hdr_compression=1
+compress/normal_map=0
+compress/channel_pack=0
+mipmaps/generate=false
+mipmaps/limit=-1
+roughness/mode=0
+roughness/src_normal=""
+process/fix_alpha_border=true
+process/premult_alpha=false
+process/normal_map_invert_y=false
+process/hdr_as_srgb=false
+process/hdr_clamp_exposure=false
+process/size_limit=0
+detect_3d/compress_to=1
+svg/scale=1.0
+editor/scale_with_editor_scale=false
+editor/convert_colors_with_editor_theme=false