feat(cli): take instance bootstrap values from the environment

[Lob26]

What changes

facility instance bootstrap reads each option from its FACILITY_<OPTION>
environment variable — --org-slug from FACILITY_ORG_SLUG — so a one-shot
container task can carry the binding without a command line. A bootstrap
Compose profile runs it:

docker compose --profile bootstrap run --rm bootstrap

Why

Binding the first owner is the one step between a started bundle and a usable
instance, and today it needs a local Node toolchain, the published CLI, and ten
flags typed correctly. The CLI already travels inside the api image for exactly
this reason — the Dockerfile says so and installs a facility wrapper on PATH
— but nothing in docker-compose.yml reached it.

Environment rather than arguments is the design decision, not a convenience.
An organization name and a GitHub login are operator input. The shape that
otherwise fits a Compose service is
sh -c "facility instance bootstrap --org-name $FACILITY_ORG_NAME …", which
interpolates that input into a command. Passing values as variables to an
exec-form command removes the shell from the path instead of quoting around it —
the same lesson as #214 and #186, where a discovered directory name and a git ref
reached a shell unquoted.

Precedence and validation are deliberate: an explicit option wins over its
variable, a malformed option fails rather than being rescued by an ambient
one, and a value is validated identically whichever way it arrived — a variable
is not more trusted for having come from the environment. Missing values are
reported under both spellings, because the operator reading that error in a
container log has only the variable.

The profile keeps bootstrap out of docker compose up, and its variables use
:- rather than :? on purpose: a required-variable interpolation is evaluated
for the whole file and would fail up itself. The CLI names what is missing.

Verification

Five new cases, deterministic without PostgreSQL or the network — the injected
client refuses at the first database call, so a run that reaches it has passed
every validation:

• an environment-only run reaches the database;
• an explicit option overrides its variable;
• a blank option still defers to the variable, and the variable is validated
  (--org-slug must be a lowercase URL slug, not accepted);
• a malformed option does not fall back to the environment; and
• the missing-value message is pinned in full, both spellings.

pnpm --filter @theagilemonkeys/facility test        14 passed, 0 skipped

That includes the pre-existing transactional/idempotency test, which normally
skips: I ran it against a real PostgreSQL rather than leaving it skipped, so the
advisory-lock and conflict paths were exercised.

The Compose profile was resolved, not assumed:

docker compose config --services
  postgres api migrate runner-image web worker          (no bootstrap)
docker compose --profile bootstrap config --services
  postgres api bootstrap migrate runner-image web worker

node guards/run.mjs                                     2 guards, 0 failed
pnpm --filter @facility/docs build                      [SUCCESS]

• pnpm verify passes locally
• Behaviour verified beyond the test suite (say how)
• Documentation updated, or no user-facing change

pnpm verify does not pass on this machine and not because of this change:
test:dev reports 116 tests, 92 pass, 24 fail here, and I measured the
identical 92/24 on a clean main — Windows noise in the patched image-size
cases, tar failing to resolve C:, and the registry publication tests. Beyond
the suite, the profile was resolved with real docker compose config runs, which
is what confirmed that :? would have broken up for everyone.

Not done on purpose: the master key is not auto-generated. It looks like the
obvious companion, and it is the wrong feature. A generated key that is not
persisted makes every stored project secret undecryptable on the next start, and
one written to a file is a secret on disk with whatever mode the writer chose.
${SECRET_MASTER_KEY:?set SECRET_MASTER_KEY} is already a good error for a value
the operator must own.

Related: #19, which asks for the operator bootstrap to be automated in a
cloud-agnostic bundle. This is that step; it does not close the issue.

🤖 Claude Code helped