feat: Count implicit tags

[bradenmacdonald]

This updates our "get tag counts" API so that the tag counts can include the implicit tags.

Currently, we have an inconsistency in how the counts are displayed in the platform:

This API change will allow us to make the counts in both places include the implicit tags (use the higher number consistently).

Private ref: FAL-3573

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[bradenmacdonald]

@ormsbee would you mind reviewing this PR?

[ChrisChV]

@ormsbee Thanks for the review! Could you merge this PR? @bradenmacdonald is on holidays :slightly_smiling_face:

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