fix(cli): activity/tui/credential/security honor global --data-dir; extract shared loadCLIConfig#909

Dumbris merged 4 commits into

mainsmart-mcp-proxy/mcpproxy-go:mainfrom

fix/908-cli-datadir-remainingsmart-mcp-proxy/mcpproxy-go:fix/908-cli-datadir-remainingCopy head branch name to clipboard