fix(dashboard): enable embedded chat by default so the GUI connects

[teknium1]

Summary

Plain hermes dashboard now produces a dashboard the GUI can actually connect to — embedded chat is on by default instead of requiring --tui.

Root cause: cmd_dashboard minted embedded_chat = args.tui or HERMES_DASHBOARD_TUI==1, so with no flag the chat WebSocket (/api/ws, /api/pty) closed every upgrade with 4403/4404 before the auth ticket was ever consumed. The desktop GUI needs that socket, so it could never connect unless the operator knew to pass --tui. PR #38743 improved the refusal messaging (split close codes, log reasons) but never flipped the default — so the connection blocker survived.

Changes

• hermes_cli/main.py: embedded chat is ON by default. --no-tui (or HERMES_DASHBOARD_TUI=0/false/off) is the explicit opt-out for hardened public binds. --tui / =1 remain as explicit-on and win over a stale =0 env.
• hermes_cli/web_server.py: start_server(embedded_chat=...) default flipped False → True so programmatic callers (desktop app) match the CLI default.
• Added --no-tui arg; --tui help updated to note default-on.

Security note

The embedded /chat PTY tab spawns a shell-capable agent. With this change it's reachable by default on any bind that passes the auth gate (ticket/internal credential + host/origin + dashboard basic-auth). Operators who bind 0.0.0.0 for a hardened deployment and don't want the in-browser shell should pass --no-tui or set HERMES_DASHBOARD_TUI=0.

Validation

Scenario	embedded_chat
hermes dashboard (no flag)	True (was False — the bug)
--host 0.0.0.0, no flag	True
--tui	True
--no-tui	False
HERMES_DASHBOARD_TUI=0 / false / off	False
--tui + stale HERMES_DASHBOARD_TUI=0	True (explicit-on wins)

10-case argparse E2E all pass. tests/hermes_cli/test_web_server.py + test_web_server_host_header.py: 238 passed (incl. test_rejects_when_embedded_chat_disabled, the explicit-disable path).

Infographic

[teknium1]

Closing as redundant. PR #38591 (cae6b54, @benbarclay) already merged the complete fix — embedded chat is unconditional and the dashboard --tui flag is removed entirely. I built this on a stale worktree base from before #38591 landed and didn't check existing PRs first; #38591 is the correct and more thorough fix (also updates the desktop electron spawn, docs, and zh-Hans translations). My apologies for the noise.