fix: update Claude.ai MCP connector instructions to current UI (#709)

Updates the en/sv claude_ai_instructions strings from 'Settings → Integrations → Add Integration' to 'Settings → Connectors → Add custom connector' to match Claude's current UI. i18n-only; no code/migration changes.

messages/en.json

@@ -1459,7 +1459,7 @@
     "copy_aria": "Copy",
     "connect_mcp_title": "Connect MCP client",
     "recommended_badge": "Recommended",
-    "claude_ai_instructions": "Go to <path>Settings → Integrations → Add Integration</path> and paste the MCP server URL. You sign in via your {connectorName} account — no API key needed.",
+    "claude_ai_instructions": "Go to <path>Settings → Connectors → Add custom connector</path> and paste the MCP server URL. You sign in via your {connectorName} account — no API key needed.",
     "claude_code_cursor": "Claude Code / Cursor",
     "terminal_runs_browser_login": "Run in the terminal — sign in via the browser:",
     "connect_with_api_key": "Connect with an API key instead",

messages/sv.json

@@ -1459,7 +1459,7 @@
     "copy_aria": "Kopiera",
     "connect_mcp_title": "Anslut MCP-klient",
     "recommended_badge": "Rekommenderat",
-    "claude_ai_instructions": "Gå till <path>Settings → Integrations → Add Integration</path> och klistra in MCP-serverns URL. Du loggas in via ditt {connectorName}-konto — ingen API-nyckel behövs.",
+    "claude_ai_instructions": "Gå till <path>Settings → Connectors → Add custom connector</path> och klistra in MCP-serverns URL. Du loggas in via ditt {connectorName}-konto — ingen API-nyckel behövs.",
     "claude_code_cursor": "Claude Code / Cursor",
     "terminal_runs_browser_login": "Kör i terminalen — loggar in via webbläsaren:",
     "connect_with_api_key": "Anslut med API-nyckel istället",