feat: friendly tool names per MCP title field or manifest

- Aggiunto campo 'title' a tools/list in tutti gli script MCP locali
  (Gmail, Gcal, Drive, Email, SSH, Weather, Wikipedia, WhatsApp)
- Aggiunto tools[]/display_name nel manifest per connector remoti/package
  esterni (Firecrawl, HTTP Fetch, Exa, Tavily, SerpAPI Flights)
- Documentata convenzione e resolution order in SKALD.md
- Aggiornata manifest_guide.md per tools[] in connectors.json
- Bumped version e sha256 per tutti i 13 connector

connectors/gcal/connector.json

@@ -54,7 +54,7 @@
   "homepage": "https://calendar.google.com",
   "icon_small": "icon_sm.svg",
   "icon_large": "icon_lg.svg",
-  "version": 1,
-  "version_string": "0.3.0",
-  "version_release_date": "2026-07-19"
-}
+  "version": 2,
+  "version_string": "0.3.1",
+  "version_release_date": "2026-07-21"
+}