feat(ui): add tag-based node color coding for lineage DAG

[CTC97]

Description

Gives users the ability to specify colors for nodes with a given tag in their config.yaml, ex:

ui:
  node_colors:
    staging: "#059669"
    mart: "#ffe291"
    exhibit: "#D97706"

When a model has multiple tags, the first match wins. Projects without ui.node_colors are unaffected — nodes render with default type-based colors.

At least somewhat related to #4363.

Test Plan

Tested locally.

Checklist

• I have run make style and fixed any issues
• I have added tests for my changes (if applicable)
• All existing tests pass (make fast-test)
• My commits are signed off (git commit -s) per the DCO

[CTC97]

Believe the failing test is flaky, but please let me know if you think otherwise.

[StuffbyYuki]

merged