feat(cli): describe sub-command (#2650)

Closes #2603 

See base PR for more context: #2639

The `describe` CLI command loads the package with a description and:
- If successful prints the description as tables to output
- If error prints partial description to output and error to stderror
- If --json flag is passed outputs as json instead, for use with other
tools


## Help
<img width="762" height="932" alt="image"
src="https://github.com/user-attachments/assets/adf53b06-652a-4967-afcb-88e9cabfaad8"
/>


## Summary
<img width="1056" height="337" alt="image"
src="https://github.com/user-attachments/assets/f0882eb3-2b80-421d-9de7-614dc4e42c7c"
/>


## JSON (nushell render)

<img width="1449" height="261" alt="image"
src="https://github.com/user-attachments/assets/7a2728cc-a0d4-417c-b938-06b26d409d47"
/>

---------

Co-authored-by: Alec Edgington <[email protected]>

Author: ss2165

Cargo.lock

@@ -91,6 +91,7 @@ pretty_assertions = "1.4.1"
 zstd = "0.13.2"
 relrc = "0.5.0"
 wyhash = "0.6.0"
+schemars = "1.0.4"
 
 # These public dependencies usually require breaking changes downstream, so we
 # try to be as permissive as possible.

Cargo.toml

@@ -21,11 +21,15 @@ clap-verbosity-flag.workspace = true
 derive_more = { workspace = true, features = ["display", "error", "from"] }
 hugr = { path = "../hugr", version = "0.24.0" }
 serde_json.workspace = true
+serde = { workspace = true, features = ["derive"] }
 clio = { workspace = true, features = ["clap-parse"] }
 anyhow.workspace = true
 thiserror.workspace = true
 tracing = "0.1.41"
 tracing-subscriber = { version = "0.3.20", features = ["fmt"] }
+tabled = "0.20.0"
+schemars = { workspace = true, features = ["derive"] }
+
 
 [lints]
 workspace = true