Add tabular output with --format flag

Tabular output is much easier to quickly scan for value, as well as
being more amenable to traditional UNIX scripting. For example,
compare finding the block_size for an image in the following output:

  $ oxide image list --format=json
  [
    {
      "block_size": 512,
      "description": "Debian 13 generic cloud image",
      "id": "3672f476-51ff-49ab-bd2c-723151a921c6",
      "name": "debian-13",
      "os": "Debian",
      "size": 3221225472,
      "time_created": "2025-08-11T16:48:17.827861Z",
      "time_modified": "2025-08-11T16:52:23.411189Z",
      "version": "13"
    }, {
      "block_size": 4096,
      "description": "Silo image for Packer acceptance testing.",
      "id": "f13b140e-4d34-4060-b898-6316cdcc2f1e",
      "name": "packer-acc-test-silo-image",
      "os": "",
      "size": 1073741824,
      "time_created": "2025-05-15T23:11:14.015948Z",
      "time_modified": "2025-05-15T23:12:02.098119Z",
      "version": ""
    }
  ]

Versus:

  $ oxide image list --format=table:name,block_size
   NAME                        BLOCK_SIZE
   debian-13                   512
   packer-acc-test-silo-image  4096

For query operations with a response type that is amenable to tabular
formatting, we add a `--format` flag to the subcommand. This takes an
optional comma-separated list of field names to print, as larger
response items can easily overflow typical terminal widths. The
available field names are listed in the `--help` output for the
subcommand.

The existing JSON format remains the default. Future changes may add the
ability to set a default format on a per-command basis.

Not all API return values can be reasonably formatted as a table.
Endpoints returning `()`, byte streams, and unstructured
`serde_json::Value` objects are deliberately excluded.

Internally, this is implemented using the newly added `ResponseFields`
trait, which xtask creates as part of the generated CLI. This enables
getting the field names of a type and accessing them as a
`serde_json::Value` via their name.

Author: wfchandler

Cargo.lock

@@ -22,6 +22,7 @@ chrono = { version = "0.4.42", features = ["serde"] }
 clap = { version = "4.5.50", features = ["derive", "string", "env", "wrap_help"] }
 clap_complete = "4.5.59"
 colored = "3.0.0"
+comfy-table = "7.2.1"
 crossterm = { version = "0.29.0", features = [ "event-stream" ] }
 dialoguer = "0.12.0"
 dirs = "6.0.0"
@@ -32,6 +33,7 @@ flume = "0.11.1"
 futures = "0.3.31"
 httpmock = "0.7.0"
 humantime = "2.3.0"
+indexmap = "2.11.3"
 indicatif = "0.18.0"
 libc = "0.2.177"
 log = "0.4.28"
@@ -44,9 +46,11 @@ oxide-httpmock = { path = "sdk-httpmock", version = "0.13.0" }
 oxnet = "0.1.3"
 predicates = "3.1.3"
 pretty_assertions = "1.4.1"
+proc-macro2 = "1.0.101"
 progenitor = { git = "https://github.com/oxidecomputer/progenitor", default-features = false }
 progenitor-client = "0.11.2"
 rand = "0.9.2"
+quote = "1.0.40"
 ratatui = "0.29.0"
 rcgen = { version = "0.14.5", features = ["pem"] }
 regex = "1.12.2"
@@ -59,6 +63,7 @@ serde = { version = "1.0.219", features = ["derive"] }
 serde_json = "1.0.145"
 similar = "2.7.0"
 support-bundle-viewer = "0.1.2"
+syn = "2.0.106"
 tabwriter = "1.4.1"
 thiserror = "2.0.17"
 tempfile = "3.23.0"

Cargo.toml

@@ -27,6 +27,7 @@ chrono = { workspace = true }
 clap = { workspace = true }
 clap_complete = { workspace = true }
 colored = { workspace = true }
+comfy-table = { workspace = true }
 crossterm = { workspace = true }
 dialoguer = { workspace = true }
 dirs = { workspace = true }