Use name field instead of username for Threads provider

[gncnpk]

What kind of change does this PR introduce?

Uses the name field from Threads Graph API instead of using the username field

Why was this change needed?

Keeps the display name consistent with other channels.

Other information:

I made a post in Discord about it.

Checklist:

Put a "X" in the boxes below to indicate you have followed the checklist;

• I have read the CONTRIBUTING guide.
• I checked that there were not similar issues or PRs already open for this.
• This PR fixes just ONE issue (do not include multiple issues or types of change in the same PR) For example, don't try and fix a UI issue and include new dependencies in the same PR.

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