feat: Create ABCI++ Verfication Methods

[alexanderbez]

Description

Closes: #15288

• Create methods that allow indirect access to runTx which will allow applications with custom ABCI++ handlers to verify transactions.
• Move default ABCI proposal handlers out into a separate struct, giving app devs an example of how to set/plugin custom handlers.

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[alexanderbez]

@tac0turtle are you chill with backporting this to v0.47.x or do you prefer to wait till 0.47.1?

[tac0turtle]

looks good to me, waiting to approve for juliens comments to be resolved

[julienrbrt]

lgtm!