Add stellar network root-account command

[mootz12]

What

Add a command to compute the root-account key in the CLI

Examples:

1. Outputs secret key or public key, uses default network of the CLI

% stellar network root-account public-key
GBZXN7PIRZGNMHGA7MUUUF4GWPY5AYPV6LY4UV2GL6VJGIQRXFDNMADI

% stellar network root-account secret
SC5O7VZUXDJ6JBDSZ74DSERXL7W3Y5LTOAMRF7RQRL3TAGAPS7LUVG3L

2. Accepts --network args

% stellar network root-account public-key --network testnet 
GBRPYHIL2CI3FNQ4BXLFMNDLFJUNPU2HY3ZMFSHONUCEOASW7QC7OX2H

3. Accepts --network-passphrase args. Prioritizes this over any configured or supplied --network. Like JS Keypair, does not fail if input is not a current passphrase.

% stellar network root-account secret --network-passphrase "Test SDF Future Network ; October 2022" 
SCR2DRVHQKDHCPRJXYHJPBLHB6UDRUJZC7GY5LVUUNLZ74O6XR75KK5K

Why

Closes: #2389

Known limitations

None

[Copilot]

Pull request overview

Adds a new stellar network root-account subcommand to derive the network root account keypair (secret by default, optional public key) directly from a network passphrase / configured network, removing the need for stellar-core convert-id pipelines.

Changes:

• Introduces network root-account command that derives the root account seed from sha256(network_passphrase) and prints either S… (default) or G… (--public-key).
• Wires the new subcommand into the network command module and updates generated help docs.
• Adds integration tests covering default behavior, flag behavior, and passphrase override precedence.

Reviewed changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
cmd/soroban-cli/src/commands/network/root_account.rs	Implements the new network root-account command and output selection logic.
cmd/soroban-cli/src/commands/network/mod.rs	Registers the new RootAccount subcommand and plumbs errors/run dispatch.
cmd/crates/soroban-test/tests/it/config.rs	Adds integration tests for the new command (default, flags, override, exclusivity).
FULL_HELP_DOCS.md	Updates CLI help docs to include network root-account (and reflects current bindings subcommands).
Cargo.lock	Updates lockfile to reflect dependency graph changes.

[leighmcculloch]

% stellar network root-account --public-key
GBZXN7PIRZGNMHGA7MUUUF4GWPY5AYPV6LY4UV2GL6VJGIQRXFDNMADI

% stellar network root-account --secret
SC5O7VZUXDJ6JBDSZ74DSERXL7W3Y5LTOAMRF7RQRL3TAGAPS7LUVG3L

Could these be separate sub-commands using names that parallel the stellar keys command?

stellar network root-account secret

stellar network root-account address|public-key

[mootz12]

Could these be separate sub-commands using names that parallel the stellar keys command?

Yep. Originally changed it to reduce code duplication, but didn't consider that this matches the stellar keys API.

[leighmcculloch]

In general too the style / flavor of the stellar-cli's command are:

• Actions are distinguished as subcommands
• Inputs / params / variables to those actions are options

That's a bit fuzzy here where we could think of a single subcommand to get the account and different views of that, but generally is implemented in the stellar-cli as on the other end of the spectrum away from DRY.

We maybe should capture this in the contributing.md.