docs(mcp): remove obsolete server creation setting

[WebMad]

Summary

• remove the obsolete Enable MCP Server Creation section and related prerequisites
• update MCP server creation guidance to reflect the current skill-based flow
• fix the MCP token-optimization link to point to the existing Enable MCP Servers setting
• remove the unused toggle screenshot and stale server creation guide reference

Validation

• searched all current documentation for the obsolete setting, identifier, anchor, and screenshot reference
• confirmed remaining mentions exist only in historical release notes
• ran git diff --check

Related to Zoo-Code-Org/Zoo-Code#895

[taltas]

@zoomote, please review this

[zoomote]

I started a PR review task for this request. See task

[zoomote]

No code issues found. See task

Verified: the fixed #enabling-or-disabling-mcp-servers anchor resolves in the production build, no stale references to the removed setting/anchor/screenshot remain outside historical release notes, and pnpm run check-types + pnpm build pass.

_{Reviewed d26a3af}

[edelauna]

Thanks for updating