Add JS snippets to Verifier Contract docs & standardize CLI commands

[thisisjoshford]

The Verifier Contract documentation needs two related improvements:

1. Standardize CLI commands to use new Rust CLI — Docs currently show a mixture of old near-cli commands and near-cli-rs commands. Although old CLI commands work as rust version has backwards compatibility, they should be updated to stay consistent across documentation

2. Add executable code snippets — Several pages have only JSON payload examples with no runnable CLI or SDK code showing how to actually submit them. Additonally, Account Abstraction has docs on authentication flow for frontends & key rotation without reference code snippets showing how they work.

Would be nice to have snippets imported from https://github.com/near-examples/near-intents-examples/ with cross-reference links.

[thisisjoshford]

Relevant -> #6 (comment)