feat: add capability to reformat Transactions before broadcasting (co…

…smos#12936)

## Description
Increase customized signing capabilities by:
- Adding a hook to preprocess transactions before broadcasting

This PR introduces the ability to preprocess transactions before broadcasting, a feature that provides the ability to add extensions, or otherwise customize the payload to satisfy a chain's requirements. For adaptability, the parameters include the keytype to allow differentiation between formatting transactions for Ledger vs. software keys.

## PR
This PR introduces a hook to preprocess transactions, chiefly to add extensions, from a higher-level chain. Key changes and relevant files:

- Add `PreprocessTxFn` type and fields to both `Context` and `Factory`
- Instantiate the `Factory` with the `PreprocessTxFn` provided by the `Context`
- Call `PreprocessTx` with the appropriate parameters after signing

Closes: #XXXX



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### Author Checklist

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please add links to any relevant follow up issues.*

I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/main/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/main/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)