fix(dashboard): discover MCP tools on startup

[kurom1ii]

Problem

The hermes dashboard command (used by the Hermes Desktop Electron app as its backend process) starts the web UI server without discovering MCP tools. Unlike the CLI chat path which calls _prepare_agent_startup(), the dashboard's cmd_dashboard() function skips this entirely because "dashboard" is not in _AGENT_COMMANDS.

This means MCP servers like github-mcp and codegraph are never connected when the dashboard starts, so the Desktop's AI agent sessions have no MCP tool access until the user manually clicks Reload MCP in Settings.

Fix

Added start_background_mcp_discovery() call from cmd_dashboard() before start_server(), using the same background-thread pattern that _prepare_agent_startup() uses for the chat command. This keeps dashboard startup fast even if an MCP server is slow to respond.

Testing

Before the fix: agent.log showed no MCP discovery during dashboard startup. After the fix:

16:22:45  MCP server 'codegraph' (stdio): registered 10 tool(s)
16:22:45  MCP server 'github-mcp' (HTTP):  registered 48 tool(s)
16:22:45  MCP: registered 58 tool(s) from 2 server(s)

MCP tools now appear in the dashboard/Desktop backend on startup without requiring manual Reload MCP.

[teknium1]

Superseded by PR #44512 — fix(desktop): discover MCP tools for dashboard /api/ws backends (commit 73969771a, merged June 11), which is now on main and resolves issue #42694.

#44512 implements the same fix this PR proposes: cmd_dashboard() spawns a background MCP discovery thread via hermes_cli.mcp_startup.start_background_mcp_discovery() before start_server(), and tui_gateway.server._make_agent() waits on that thread before snapshotting tools. Verified on current main.

Thanks for the fix — closing as redundant. Credit to you and the other contributors who independently caught this (#42703, #43189, #40407 all targeted the same gap).