fix(service-party-app): 移除不兼容的@types/bech32

bech32 v2.0.0 自带TypeScript类型定义，不需要单独的
@types/bech32 包（该包是针对v1.x版本的）。

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/mpc-system/services/service-party-app/package-lock.json

@@ -28,7 +28,6 @@
         "zustand": "^4.4.7"
       },
       "devDependencies": {
-        "@types/bech32": "^1.1.2",
         "@types/express": "^4.17.21",
         "@types/node": "^20.10.0",
         "@types/react": "^18.2.39",
@@ -2449,16 +2448,6 @@
         "@babel/types": "^7.28.2"
       }
     },
-    "node_modules/@types/bech32": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/@types/bech32/-/bech32-1.1.2.tgz",
-      "integrity": "sha512-D2tG6kfIcZD3pjtnnvGrwiZiz+HGBsoy0pdGlpBeMbhlKJ4l4r1zB8SEQPL790kTdSS8lhyC/w9API7L2YBOxw==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "@types/node": "*"
-      }
-    },
     "node_modules/@types/body-parser": {
       "version": "1.19.6",
       "resolved": "https://registry.npmjs.org/@types/body-parser/-/body-parser-1.19.6.tgz",

backend/mpc-system/services/service-party-app/package.json

@@ -37,7 +37,6 @@
     "zustand": "^4.4.7"
   },
   "devDependencies": {
-    "@types/bech32": "^1.1.2",
     "@types/express": "^4.17.21",
     "@types/node": "^20.10.0",
     "@types/react": "^18.2.39",