feat: complete remaining Go backend modules

contracts/assets/http-v1.json

@@ -0,0 +1,34 @@
+{
+  "version": 1,
+  "limits": { "jsonBytes": 1048576, "uploadBytes": 20971520, "remoteBytes": 20971520 },
+  "errors": {
+    "platformNotFound": { "status": 404, "body": { "error": "资产不存在" } },
+    "platformNotDownloadable": { "status": 404, "body": { "error": "资产文件不可下载" } },
+    "publicNotFound": { "status": 404, "body": { "error": "Asset not found." } },
+    "publicNotDownloadable": { "status": 404, "body": { "error": "Asset file is not downloadable." } },
+    "noFiles": { "status": 400, "body": { "error": "No files uploaded." } },
+    "tooLarge": { "status": 413, "body": { "error": "Request body is too large." } },
+    "internal": { "status": 500, "body": { "error": "Internal server error." } }
+  },
+  "methods": {
+    "headExecutesGet": true,
+    "optionsStatus": 204,
+    "unsupportedStatus": 405,
+    "unsupportedBody": "empty"
+  },
+  "binary": {
+    "downloadCacheControl": "private, no-store",
+    "servedCacheControl": "public, max-age=31536000, immutable"
+  },
+  "routes": [
+    { "path": "/api/assets", "allow": "GET, HEAD, POST, OPTIONS" },
+    { "path": "/api/assets/upload", "allow": "POST, OPTIONS" },
+    { "path": "/api/assets/{id}", "allow": "DELETE, OPTIONS" },
+    { "path": "/api/assets/{id}/download", "allow": "GET, HEAD, OPTIONS" },
+    { "path": "/api/v1/assets", "allow": "GET, HEAD, POST, OPTIONS" },
+    { "path": "/api/v1/assets/{id}", "allow": "GET, HEAD, OPTIONS" },
+    { "path": "/api/v1/assets/{id}/download", "allow": "GET, HEAD, OPTIONS" },
+    { "path": "/uploads/{path...}", "allow": "GET, HEAD, OPTIONS" },
+    { "path": "/generated-results/{path...}", "allow": "GET, HEAD, OPTIONS" }
+  ]
+}