Get a plan to consolidate messy Drip tags

**Objective:** Audit the tags in Drip, optionally limited to tags containing `{tag-contains}`, and find duplicates, unused tags and naming drift.

**Step 1: List tags**

Call `drip-get-tag` with `max-records` = 500, and `tag.contains` = `{tag-contains}` only if given.

**Step 2: Group near-duplicates**

Group tags that differ only by case, spacing, punctuation, plural vs singular or an obvious typo (Customer, customer, Customers, Cusotmer).

**Step 3: Measure usage**

For each tag in a near-duplicate group, and for up to 30 other tags, call `drip-get-subscriber` with `tags.contains` set to the tag and `max-records` = 50. Record the count, reporting 50 as 50+.

**Step 4: Report**

* **Near-duplicates:** each group, the count per variant, and which variant to keep (the most used, in the dominant naming style)
* **Unused:** tags with 0 people
* **Naming style:** the dominant convention (case, separators, prefixes such as source: or interest:) and the tags that break it
* **Cleanup plan:** for each tag to retire, the tag to move people to

**Rules & Guidelines:**

* Read-only. Do NOT call `drip-add-subscriber-tag` or `drip-remove-subscriber-tag`. Retagging is a bulk change the user must approve; recommend it, do not perform it.
* No tool deletes a tag; say that unused tags must be removed in Drip itself.

**Validation:**

* If there are no tags, say so and stop.
* Note that tags.contains is a substring match, so short tags can over-count; flag any count that looks inflated for that reason.