docs.json nav is stale — missing telemetry/context entry, CLI pages wiped on build

[ajbozarth]

The docs nav (docs/docs/docs.json) has two stale entries that surface when the doc site is built:

1. api/mellea/telemetry/context missing from nav — the context module was added in feat: first pass at carrying contextvars though async flows #878 but the nav was never updated.

2. cli group wiped to empty "pages": [] on build — the CLI reference MDX files appear to be stale or missing; running uv run poe clidocs to regenerate them first should fix this.

Neither is urgent but worth fixing in the next PR that touches either area.

[planetf1]

If there are detectable failures during build that we do not detect I suggest raising an additional issue to address the root cause

[ajbozarth]

If there are detectable failures during build that we do not detect I suggest raising an additional issue to address the root cause

This was caught when rebuilding the docs locally, so we could possibly add a doc rebuild step to the CI that checks that it doesn't edit files