ICS24 Identifier and Path validation

[fedekunze]

Summary

Implement a generalized Identifier and Path validation functions as defined in ICS24.

This is required by most of the IBC msg validation functions.

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[cwgoes]

I assume you mean validation of client, connection, and channel identifiers. Those are separate; they don't need to perform the same validation (but they can).

I think, for now, it's fine if those three all perform the same simple checks:

• Length bounds (at least 10 characters, at most 20 characters - to prevent name squatting)
• Character inclusion (alphanumeric only, maybe prohibit uppercase)

[fedekunze]

@AdityaSripal FYI the PR should be rebased to joon/ics-23-implementation

[fedekunze]

Closed via #5229