fix: always overwrite api_server config on startup

Simplify ensureApiServerConfig to unconditionally write default
platforms.api_server values, preventing missing config issues.

Bump version to 0.2.7.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "hermes-web-ui",
-  "version": "0.2.6",
+  "version": "0.2.7",
   "description": "Web dashboard for Hermes Agent — multi-platform AI chat, session management, scheduled jobs, usage analytics & channel configuration (Telegram, Discord, Slack, WhatsApp)",
   "repository": {
     "type": "git",
@@ -85,4 +85,4 @@
     "vite": "^8.0.4",
     "vue-tsc": "^3.2.6"
   }
-}
+}