docs(changelog): note the anchor-expansion bomb fix

CHANGELOG.md

@@ -429,6 +429,23 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `Tagged.Dumper` honors `sortKeys` in its block and canonical paths for
   mappings whose keys are all plain, untagged, unanchored string scalars,
   matching the model dumper's `orderedPairs` rule.
+- `parse`/`parseStreaming` now reject an anchor-expansion ("billion
+  laughs") bomb instead of accepting it in milliseconds and handing a
+  caller a value whose logical size is exponential in the alias nesting
+  depth. `enforceNestingLimit` bounds physical collection depth in the
+  raw event stream, which does nothing against a handful of shallow,
+  small anchors each aliased many times with each alias nested inside
+  the next: a 25-level, fan-out-9 document (~1.5KB) expands past 9^25
+  logical nodes while raw event depth stays at 2. `EventStreamComposer`
+  now charges a total expanded-node budget incrementally as the document
+  streams through -- every scalar, alias resolution, and completed
+  container charges its own marginal cost, with each anchor's expanded
+  size cached at definition and looked up in O(1) when later aliased --
+  so a bomb is rejected within a few alias levels without ever
+  materializing or walking the exponential tree it would otherwise
+  produce. A document with genuinely wide but non-exponential alias
+  reuse (the same anchor referenced thousands of times at one level, no
+  nesting) still parses normally.
 
 ## [0.2.0] - 2026-07-05