fix: correct schema documentation errors

[ivan-aksamentov]

Fix documentation errors discovered during schema review: incorrect enum values, stale TODOs, missing fields, and wrong field types.

• Use cdsName instead of geneName in QC examples
• Replace stale aaMutLabelMap TODO with actual documentation
• Correct searchAlgo enum value ancestor-latest to ancestor-nearest
• Mark clade_node_attrs displayName as required per schema
• Add missing fields to pathogen config documentation
• Correct ref_nodes field types and add missing qry[].name

1. Depends on: docs: add documentation comments to JSON schema types #1757
2. Related to: fix: correct documentation errors in dataset guides nextclade_data#415

[github-actions]

Preview: https://nextstrain--nextclade--pr-1758.previews.neherlab.click

(ci)