refactor(StorageRegistry): rename ADMIN role to OWNER

[varunsrin]

Motivation

The role that performs the majority of administrative functions is called the owner in most contracts except for the StorageRegistry, which refers to it as admin. This PR standardizes the naming to owner.

Change Summary

• Rename the ADMIN role to OWNER in StorageRegistry

Merge Checklist

• [x] The PR title adheres to the conventional commits standard
• [x] The PR has been tagged with change type label(s) (i.e. documentation, feature, bugfix, or chore)
• [x] The PR's changes adhere to all the requirements in the contribution guidelines
• [x] This PR does not require changes to the Farcaster protocol

[github-actions[bot]]

Coverage after merging varunsrin/rename-storage-admin-owner into main will be

98.70%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
src
Bundler.sol	100%	100%	100%	100%
FnameResolver.sol	100%	100%	100%	100%
IdRegistry.sol	100%	100%	100%	100%
KeyRegistry.sol	100%	100%	100%	100%
StorageRegistry.sol	100%	100%	100%	100%
src/lib
Signatures.sol	100%	100%	100%	100%
TransferHelper.sol	0%	0%	0%	0%	15, 15, 15, 25–26, 26, 26
TrustedCaller.sol	100%	100%	100%	100%