`gaia-emr dashboard` serves a bare API response when the frontend isn't built; EMR guide doesn't document `npm build` step

[itomek]

gaia-emr dashboard is documented to launch a desktop/web dashboard. On a fresh developer install, it silently serves an API-only response in the browser because the frontend hasn't been built. The response body itself says the frontend isn't built.

Reproduction

PS> gaia-emr dashboard
# Browser opens to http://localhost:<port>/ and shows:
{"message":"EMR Dashboard API is running","frontend":"not built (run npm build in dashboard/frontend)","api_docs":"/docs"}

Two problems

1. Docs gap — docs/guides/emr.mdx doesn't tell the user to run npm build in dashboard/frontend/ before launching the dashboard. Same shape as Use public Lemonade hybrid installer #2's missing-extras pattern.
2. CLI UX bug — the command knows the frontend isn't built (the message says so) but launches anyway. It should either build on demand, fail loud with the build instruction, or at minimum surface the missing-frontend state without saying "is running."

Also on the same guide: docs/guides/emr.mdx links to https://github.com/amd/gaia/tree/main/src/gaia/agents/emr for "sample intake forms," but that directory contains no intake forms.

Fix

Docs: add a Build-the-frontend step (or fold into #6's Prerequisites template). CLI: build the frontend automatically on first launch, OR raise a clear error referencing the build step. Locate or remove the sample intake forms link.

Severity rationale

P1 — documented feature is silently non-functional on a clean install.

[github-actions]

Confirmed — all three findings reproduce in main.

🟡 CLI UX bug: src/gaia/agents/emr/dashboard/server.py:2129-2150 is exactly the silent-fallback pattern. When frontend/dist/ is missing, the / route returns the placeholder JSON ("EMR Dashboard API is running") and the server keeps running. Per CLAUDE.md's "No Silent Fallbacks" rule, this should raise an actionable error at startup (or build on demand) — name what's missing, where to build it, and which extras to install. cmd_dashboard at src/gaia/agents/emr/cli.py:1052 should check frontend/dist/ exists before calling run_dashboard().

🟢 Docs gap: docs/guides/emr.mdx:458-476 does have a "Dev Install: Build the frontend" accordion, but only inside the Desktop App tab and collapsed by default — easy to miss on a fresh uv pip install -e ".[dev,api,rag]". Worth surfacing in Prerequisites for the Dev tabs (Steps 4–5).

🟢 Broken sample-forms link: confirmed — docs/guides/emr.mdx:325 and :455 both point to src/gaia/agents/emr/, which contains only agent.py, cli.py, constants.py, __init__.py, and dashboard/. No sample forms. Either move/add forms under that path or remove the link.

Happy to take a swing at the CLI fix if no one's already on it.