* feat: you can now construct a `Transaction` with durable nonce information
* chore: refactor confirmation logic so that each strategy gets its own method
* feat: `geNonce` now accepts a `minContextSlot` param
* feat: a nonce-based transaction confirmation strategy
* feat: add nonce confirmation strategy to send-and-confirm helpers
* fix: nits from July 8 review
* Use Typescript narrowing to determine which strategy to use
* Double check the signature confirmation against the slot in which the nonce was discovered to have advanced