## MODIFIED Requirements

### Requirement: Unique identifier for every clickable item
Every clickable item that is tracked MUST have a stable identifier (`target_id`) that is unique across the site (or unique within a documented namespace).

The identifier MUST be deterministic across builds for the same element and placement.

The taxonomy MUST define namespaces for repeated UI surfaces. For the blog surface, the following namespaces MUST be used:
- `blog.subnav.*` for secondary navigation links
- `blog.card.post.<slug>` for blog post cards
- `blog.pages.link.<slug>` for blog page listing links
- `blog.post.*` / `blog.page.*` for detail page chrome links (e.g., back links)

#### Scenario: Two links in different placements
- **WHEN** two links point to the same destination but appear in different placements
- **THEN** their `target_id` values are different so their clicks can be measured independently

