Updating behaviour of VaultsSecretsGet to align with requirements of secrets cat

[aryanjassal]

Description

The current VaultsSecretsGet only gets a single secret from the vault, and returns it in the form of a UnaryHandler, meaning for large files, the RPC call will timeout. It also fetches only one file at a time, so behaviour like UNIX's cat command isn't possible.

This PR aims to fix that issue by switching over the RPC handler to a ServerHandler, supporting larger files. This PR also adds support for listing the contents of multiple files in order, like what cat does.

Issues Fixed

• Relates to Implement secrets cat command Polykey-CLI#243
• Closes ENG-356 (link)

Tasks

• 1. Switch UnaryHandler to StreamHandler
• 2. Implement support for displaying contents of multiple files
• 3. Implement support for listing multiple files across multiple vaults
• 4. Update old test and add new tests

Final checklist

• Domain specific tests
• Full tests
• Updated inline-comment documentation
• Lint fixed
• Squash and rebased
• Sanity check the final build

[linear]

ENG-356 Implement `secrets cat` command

[aryanjassal]

I have implemented basic functionality for displaying file contents for multiple files, and updated the tests in tests/client/handlers/vaults.test.ts.

I still need to review the issue spec and all the code to ensure everything's ready for review.

[aryanjassal]

MatrixAI/Polykey-CLI#243 (comment)

I'm going to go ahead with the assumption that we need to implement support for listing contents for files from multiple vaults concurrently, as that makes sense and retains consistency with UNIX commands and secrets rm.

I will wait for review of my approach from secrets rm, and if my implementation seems correct, I will implement that in secrets cat too.

[aryanjassal]

The naming of secret commands has changed from what it was. The intention was to keep using the pattern of SecretsGet, SecretsPut, SecretsDel, but to better align with the new commands, these names have been changed to SecretsGet (I haven't changed this name yet), SecretsEdit, SecretsRemove.

We are kinda moving away from the pattern. This was hard to detect as this change was made one-at-a-time across multiple PRs. We might need to look into this and set a standard pattern to follow for ensuring consistency.

[tegefaulkes]

Small changes, just check your tests are only testing the specific condition we want.