Fix sessionless HumanAgent chat functionality

- Remove session management complexity from MCP server and UI
- Update chatWebviewProvider for direct messaging without sessions
- Fix MCP tool response format to use content array as per specification
- Restore cog icon for MCP configuration (install global/local)
- Add safety checks for message content handling
- Resolve 'o.content is not iterable' error by using proper MCP format

.gitignore

@@ -0,0 +1,5 @@
+out
+dist
+node_modules
+.vscode-test/
+*.vsix