port setupManager, setupProtocol to serviceFeature

remove styles on webapp UI, and add stylesheet

package.json

@@ -68,6 +68,7 @@
         "@tsconfig/svelte": "^5.0.8",
         "@types/deno": "^2.5.0",
         "@types/diff-match-patch": "^1.0.36",
+        "@types/markdown-it": "^14.1.2",
         "@types/node": "^24.10.13",
         "@types/pouchdb": "^6.4.2",
         "@types/pouchdb-adapter-http": "^6.1.6",
@@ -134,6 +135,7 @@
         "diff-match-patch": "^1.0.5",
         "fflate": "^0.8.2",
         "idb": "^8.0.3",
+        "markdown-it": "^14.1.1",
         "minimatch": "^10.2.2",
         "node-datachannel": "^0.32.1",
         "octagonal-wheels": "^0.1.45",