forgetest: the setup suite, and the sensors check asks nothing

The commission.* tests are setup.* (subsystem "setup"): suite/setup.py,
setup_dark.py, setup_sheet.py, and the host tests test_setup_*.py. The
coverage maps name src/setup.* in place of src/commission.*, the record
is setup.json, and the bench seed in forgetest.init creates
/run/forgefirm/setup-override.

setup.check-sensors follows the check as it is now: no question is
asked and no setting is written. The test reads the settings before
and after and fails on any change, and fails at once if the check
opens a prompt. The host test drives the fake daemon with no prompt
and proves both outcomes.

Proof: test_setup_dark.py, test_setup_sheet.py, and
test_setup_suite.py pass (46 tests). The coverage lint names
src/commission.c and .h as uncovered until the forgectrl pin moves to
the revision that carries the rename.

forgetest/forgetest/suite/camera.py

@@ -396,7 +396,7 @@ def lid_privacy(ctx):
                   "authorizes a write; a rotation from the panel route stops the old key and "
                   "the new one reads. The setting is put back after.")
 def key_read(ctx):
-    from .commission import request
+    from .setup import request
     from .forgectrl import lan_ip
     fc = ctx.forgectrl
     ev = ctx.evidence