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## 4.15.4

**`(fix):`** Fix cross-reference links in C++ library documentation. Entity pages
now use relative links resolved via an entity registry, template
specializations link to their dedicated pages on index pages, namespace
index links are properly slugified, and operator method anchors use
deterministic safe names to avoid collisions.

## 4.15.3

**`(fix):`** Fix `fern generator upgrade` failing with `ENOENT` on `package.json`
when multiple CLI processes run concurrently (e.g., in parallel tests).
A cross-process file lock now serializes npm installs to the shared
`~/.fern/migration-cache` prefix, preventing concurrent install races.