feat(theme): 尝试适配 1.0.5 更新，实现背景自定义功能

- 新增主题配置项，允许用户通过 Komari 后台自定义背景图片、切换时间和过渡效果。
- 更新 GitHub Actions 发布流程，改用 `softprops/action-gh-release@v2` 以简化发布和资产上传步骤。
- 为国旗图片添加懒加载（`loading="lazy"`），优化页面加载性能。

komari-theme.json

@@ -1,9 +1,42 @@
 {
-    "name": "Komari Theme PurCarte",
+    "name": "Komari Theme PurCart",
     "short": "PurCarte",
     "description": "A frosted glass theme for Komari",
-    "version": "0.1.2",
+    "version": "0.1.3",
     "author": "Montia & Gemini",
     "url": "https://github.com/Montia37/Komari-theme-purcarte",
-    "preview": "preview.png"
+    "preview": "preview.png",
+    "configuration": {
+        "type": "managed",
+        "data": [
+            {
+                "name": "背景",
+                "type": "title"
+            },
+            {
+                "key": "backgroundImage",
+                "name": "背景图片链接",
+                "type": "string",
+                "required": false,
+                "default": "https://i.yon.li/w/682f73d97eade.png",
+                "help": "多张图片请以英文逗号分隔（eg:https://img.com/1.png,https://test.com/2.jpg）"
+            },
+            {
+                "key": "switchTime",
+                "name": "切换时间（秒）",
+                "type": "number",
+                "required": false,
+                "default": 10,
+                "help": "背景图片切换的时间间隔，单位为秒（仅设置多张图片时生效）"
+            },
+            {
+                "key": "transition",
+                "name": "背景切换过渡效果",
+                "type": "string",
+                "required": false,
+                "default": "background-image 0.8s ease-in-out",
+                "help": "CSS 过渡效果，用于背景图片切换时的动画效果（仅设置多张图片时生效）"
+            }
+        ]
+    }
 }