[nexus] Expunge disk internal API, omdb commands

[smklein]

Provides an internal API to remove disks, and wires it into omdb. Additionally, expands omdb commands for visibility.

• omdb db physical-disks can be used to view all "control plane physical disks". This is similar to, but distinct from, the omdb db inventory physical-disks command, as it reports control plane disks that have been adopted in the control plane. This command is necessary for identifying the UUID of the associated control plane object, which is not observable via inventory.
• omdb nexus sleds expunge-disk can be used to expunge a physical disk from a sled. This relies on many prior patches to operate correctly, but with the combination of: [sled-agent] Stop self-managing physical disks #5987, [Sled Agent] Expunged disks are not in use after omicron_physical_disks_ensure #5965, Allow Nexus to specify Zone filesystem location #5931, Expunge zones when their transient filesystem pools are expunged #5952, [reconfigurator] Only place Crucible zones on provisionable zpools #5601, [nexus] Remove zones on expunged disks #5599, we can observe the following behavior: expunging a disk leads to all "users" of that disk (zone filesystems, datasets, zone bundles, etc) being removed.

I tested this PR on a4x2 using the following steps:

# Boot a4x2, confirm the Nexus zone is running
# From g0, zlogin oxz_switch

$ omdb db sleds

SERIAL  IP                             ROLE      POLICY      STATE   ID                                   
 g2      [fd00:1122:3344:103::1]:12345  -         in service  active  29fede5f-37e4-4528-bcf2-f3ee94924894 
 g0      [fd00:1122:3344:101::1]:12345  scrimlet  in service  active  6a2c7019-d055-4256-8bad-042b97aa0e5e 
 g1      [fd00:1122:3344:102::1]:12345  -         in service  active  a611b43e-3995-4cd4-9603-89ca6aca3dc5 
 g3      [fd00:1122:3344:104::1]:12345  scrimlet  in service  active  f62f2cfe-d17b-4bd6-ae64-57e8224d3672

# We'll plan on expunging a disk on g1, and observing the effects.
$ export SLED_ID=a611b43e-3995-4cd4-9603-89ca6aca3dc5
$ export OMDB_SLED_AGENT_URL=http://[fd00:1122:3344:102::1]:12345
$ omdb sled-agent zones list

    "oxz_cockroachdb_b3fecda8-2eb8-4ff3-9cf6-90c94fba7c50"
    "oxz_crucible_19831c98-3137-4af4-a93d-fc1a17c138f2"
    "oxz_crucible_6adcb8ec-6c9e-4e8a-a8d4-bbf9ad44e2c4"
    "oxz_crucible_74b2f587-10ce-4131-97fd-9832c52c8a41"
    "oxz_crucible_9e422508-f4d5-4c24-8dde-0080c0916419"
    "oxz_crucible_a47e9625-d189-4001-877a-cc3aa5b1f3eb"
    "oxz_crucible_pantry_c3b4e3cb-3e23-4f5e-921b-04e4801924fd"
    "oxz_external_dns_7e669b6f-a3fe-47a9-addd-20e42c58b8bb"
    "oxz_internal_dns_1a45a6e8-5b03-4ab4-a3db-e83fb7767767"
    "oxz_ntp_209ad0d0-a5e7-4ab8-ac8f-e99902697b32"
    "oxz_oximeter_864efebb-790f-4b7a-8377-b2c82c87f5b8"

$ omdb db physical-disks | grep $SLED_ID
 ID                                    SERIAL                 VENDOR            MODEL               SLED_ID                               POLICY      STATE
 23524716-a331-4d57-aa71-8bd4dbc916f8  synthetic-serial-g1_0  synthetic-vendor  synthetic-model-U2  a611b43e-3995-4cd4-9603-89ca6aca3dc5  in service  active 
 3ca1812b-55e3-47ed-861f-f667f626c8a0  synthetic-serial-g1_3  synthetic-vendor  synthetic-model-U2  a611b43e-3995-4cd4-9603-89ca6aca3dc5  in service  active 
 40139afb-7076-45d9-84cf-b96eefe7acf8  synthetic-serial-g1_1  synthetic-vendor  synthetic-model-U2  a611b43e-3995-4cd4-9603-89ca6aca3dc5  in service  active 
 5c8e33dd-1230-4214-af78-9be892d9f421  synthetic-serial-g1_4  synthetic-vendor  synthetic-model-U2  a611b43e-3995-4cd4-9603-89ca6aca3dc5  in service  active 
 85780bbf-8e2d-481e-9013-34611572f191  synthetic-serial-g1_2  synthetic-vendor  synthetic-model-U2  a611b43e-3995-4cd4-9603-89ca6aca3dc5  in service  active 

# Let's expunge the "0th" disk here.

$ omdb nexus sleds expunge-disk 23524716-a331-4d57-aa71-8bd4dbc916f8 -w
$ omdb nexus blueprints regenerate -w
$ omdb nexus blueprints show $NEW_BLUEPRINT_ID

# Observe that the new blueprint for the sled expunges some zones -- minimally,
# the Crucible zone -- and no longer lists the "g1_0" disk. This should also be
# summarized in the blueprint metadata comment.

$ omdb nexus blueprints target set $NEW_BLUEPRINT_ID enabled -w
$ omdb sled-agent zones list

zones:
    "oxz_crucible_19831c98-3137-4af4-a93d-fc1a17c138f2"
    "oxz_crucible_74b2f587-10ce-4131-97fd-9832c52c8a41"
    "oxz_crucible_9e422508-f4d5-4c24-8dde-0080c0916419"
    "oxz_crucible_a47e9625-d189-4001-877a-cc3aa5b1f3eb"
    "oxz_crucible_pantry_c3b4e3cb-3e23-4f5e-921b-04e4801924fd"
    "oxz_ntp_209ad0d0-a5e7-4ab8-ac8f-e99902697b32"
    "oxz_oximeter_864efebb-790f-4b7a-8377-b2c82c87f5b8"

# As we can see, the expunged zones have been removed.
# We can also access the sled agent logs from g1 to observe that the expected requests have been sent
# to adjust the set of control plane disks and expunge the expected zones.

This is a major part of #4719
Fixes #5370

[sunshowers]

Looks good!

[andrewjstone]

Sorry for the delay! Looks awesome :)