Improve AI Catalog metrics: Where context is single item always track item ID, and foundational properties
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### About
Some of our events in `ee/config/events/` (search for `"ai_catalog"`) operate on single items and currently all capture the AI catalog `item` type.
But we are missing more specific information about the item that would let us filter/splice the data by
- Event data filtered for a specific custom item
- Event data filtered for a specific foundational item
- Event data filtered by foundational items as a whole
- Event data filtered by custom items as a whole
### Proposal
Update our events that fire where there is a single item in context, ensuring they all track:
| Property key name | Description |
| ------ | ------ |
| `item_id` | (Numeric\|null) The item's PostgreSQL ID (some events do track this already). Note, value will be `null` for any foundational item that does not exist in the database (example: some foundational agents). |
| `foundational_item_ref` | (String\|null) The item's "foundational item reference", when the item is a foundational item. Note, value will be `null` when item is not foundational. |
| `foundational` | (Boolean) A boolean that is `true` when item is foundational and `false` when not. |
For example, see https://gitlab.com/gitlab-org/gitlab/-/merge_requests/224303 that adds `foundational` (boolean) and `foundational_item_ref` (string) to an existing event.
At the time of writing (March 2026), the metrics we can apply these to are:
- `click_enable_ai_catalog_item_button`
- `click_duplicate_ai_catalog_item_button`
- `click_disable_ai_catalog_item_button`
- `click_delete_ai_catalog_item_button`
- `view_ai_catalog_item`
- `view_ai_catalog_project_managed`
- `create_ai_catalog_item_consumer`
- `update_ai_catalog_item_consumer`
- `delete_ai_catalog_item_consumer`
- `create_ai_catalog_item`
- `update_ai_catalog_item`
- `delete_ai_catalog_item`
- `trigger_ai_catalog_item` (being updated in https://gitlab.com/gitlab-org/gitlab/-/merge_requests/224303)
Note, the existing issue https://gitlab.com/gitlab-org/gitlab/-/work_items/578615+ can be responsible for adding this to item consumer events if it is implemented after this one.
See https://docs.gitlab.com/development/internal_analytics/internal_event_instrumentation.
issue