feat: Add metadataIpfsHash to StakingViewer Pool struct

[rackstar]

Context

Add a new field metadataIpfsHash to StakingViewer Pool struct

Changes proposed in this pull request

• Add a new field metadataIpfsHash to StakingViewer Pool struct
• add missing view modifier to StakingProducts.getPoolMetadata
• small lint fixes (spaces, modifier ordering)

Test plan

• add unit test

Checklist

• Rebased the base branch
• Attached corresponding Github issue
• Prefixed the name with the type of change (i.e. feat, chore, test)
• Performed a self-review of my own code
• Followed the style guidelines of this project
• Made corresponding changes to the documentation
• Didn't generate new warnings
• Didn't generate failures on existing tests
• Added tests that prove my fix is effective or that my feature works

Review

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• 🍰 = Nice to have but not essential.
• 💡 = Suggestion or a comment based on personal opinion
• 🔨 = I believe this should be changed.
• 🤔 = I don’t understand something, do you mind giving me more context?
• 🚀 = Feedback