A python-runner service ran from a tool venv (uv tool install --editable),
separate from the project venv that uv sync manages. The editable link kept
source live, but dependencies were resolved independently in each venv, so a
new dependency landed in the project venv and never reached the running
service — leaving no clean rollout for it.
Deploy now emits ExecStart=uv run --project <source> --no-dev <program>,
running the service in place from its own project venv. uv run syncs the env
to the lockfile before launching, so a single restart picks up both code and
dependency changes; the ExecStart is deterministic from source and never goes
stale. The tool-venv install is gated to the command runner only; uv tool
install is reserved for tool-behavior programs, where PATH is the point. A
python service with no resolvable source falls back to a PATH lookup.
