feat: users should sign message to upload stems

[Harsh8196]

General Changes

• User should sign message while uploading stems

Developer Notes

• This signed message is stored in local storage. If the user signs this message already then the user is able to upload stems if not then the user should sign the message before uploading stems.
• All signed messages are stored using key-value pair (Address: Signed Message) in local storage.

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Author Checklist

• [ ] The base branch is set to main
• [ ] The title is using Conventional Commit formatting
• [ ] The Github issue has been linked to the PR in the Development section
• [ ] The General Changes section has been filled out
• [ ] Developer Notes have been added (optional)

Reviewer Checklist

• [ ] End-to-end tests are passing without any errors
• [ ] Code style generally follows existing patterns
• [ ] New third-party packages, if any, do not introduce potential security threats
• [ ] There are no CI changes, or they have been OK’d by the devops team
• [ ] Code changes have been quality checked in the ephemeral URL
• [ ] There is at least one approval from the core team
• [ ] Squash and merge has been checked

[drewcook]

@Harsh8196 Please go over the checklist items and ensure you complete them for future PRs. Linking the issue in development section, using proper conventional commit PR titles, etc

Code looks good, nice work!