Implement "content based" grouping of user reports

This work will include the following:

• Cluster existing reports and create buckets based on clusters.
• Assign incoming reports to existing clustered buckets or create new ones.
• Come up and implement bucket prioritization score / sorting mechanism
• Add a button to remove a report from bucket or assign to another bucket
• Add an ability to refine a clustered bucket using Gemini, probably a button in the UI. It could be used if a bucket contains reports that don't match the majority of the group or just doesn't make sense in general. It could potentially look for similar reports in other buckets for this domain. We should display results for user confirmation.
• Once a bug is confirmed/filed use Gemini to find similar reports in other buckets for this domain and also display results to confirm (maybe only do that if a bucket wasn't refined previously).

The issue names no files, tests, or entry points. Start by locating the existing report clustering, bucket UI, and Gemini integration, then separate the three unchecked behaviors into an agreed scope. Done means users can remove or reassign reports, refine buckets with confirmation, and review suggested similar reports after bug confirmation.