[DOC][Tempo 3.0] Remove compactor from docs

[knylander-grafana]

What this PR does:

Summary of Documentation Changes for Tempo 3.0

Documentation updated to reflect Tempo 3.0 breaking changes from PRs 6283 and 6273. The compactor component is removed; compaction is handled by the backend scheduler and worker. The v2 block encoding is removed; only Parquet formats (vParquet3, vParquet4, vParquet5) are supported. Deployment targets were consolidated: all-3.0 merged into all, and scalable-single-binary was removed.

Key Documentation Updates:

• Configuration: Removed compactor configuration section and updated references to scheduler/worker
• Operations: Updated polling, consistent hash ring, and backend search docs to replace compactor references with worker/scheduler
• API Documentation: Removed compactor ring endpoint and compactor from memberlist table
• Troubleshooting: Updated bad-blocks, too-many-jobs-in-queue, and out-of-memory-errors docs to reference workers instead of compactors
• Block Format: Updated parquet configuration to note v2 format removal in 3.0
• Deployment Modes: Updated references to note scalable single binary mode removal in 3.0

Files Modified: 11 documentation files updated to reflect these architectural changes, ensuring users have accurate guidance for migrating to Tempo 3.0.

Addresses changes from PR #6283 and #6273

Which issue(s) this PR fixes:
Fixes https://github.com/grafana/tempo-squad/issues/1044

Checklist

• Tests updated
• Documentation added
• CHANGELOG.md updated - the order of entries should be [CHANGE], [FEATURE], [ENHANCEMENT], [BUGFIX]

[knylander-grafana]

@mapno FYI. Addresses the changes from Joe's PRs for the compactor removal.