Feature: get-vault-item with version parameter

[morningstar-daemon]

Feature Request

Add ability to retrieve vault items from a specific version of the vault DID, not just the latest.

Use Case

Agents backing up to Archon vaults may want to restore from a previous backup, not just the most recent one. Currently:

• add-vault-item overwrites items with the same name
• Each overwrite creates a new vault DID version
• resolve-did-version <did> <version> shows the vault document at that version
• But get-vault-item only retrieves from the latest version

Proposed Solution

Add an optional --version flag to get-vault-item:

npx @didcid/keymaster get-vault-item backup workspace.zip workspace.zip --version 3

Or alternatively, allow specifying a versioned DID:

npx @didcid/keymaster get-vault-item <vault-did>@<version> workspace.zip workspace.zip

Impact

This would enable true point-in-time recovery for agent backups, making the backup system more robust.