chore(flat): add changelog entry for consClose fix

Unisay · Unisay · commit 929cfd064af7 · 2026-03-20T15:45:04.000+01:00
diff --git a/plutus-core/changelog.d/20260320_154057_yuriy.lazaryev_issue_7542_flat_enum_bug.md b/plutus-core/changelog.d/20260320_154057_yuriy.lazaryev_issue_7542_flat_enum_bug.md
@@ -0,0 +1,3 @@
+### Fixed
+
+- Fixed `consClose` in the Flat decoder failing to advance the stream pointer past 1 byte, which corrupted decoder state for Generic-derived Flat instances of large enums (>256 constructors) and caused infinite memory consumption during deserialization.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+### Fixed`
	`2`	`+`
	`3`	+- Fixed `consClose` in the Flat decoder failing to advance the stream pointer past 1 byte, which corrupted decoder state for Generic-derived Flat instances of large enums (>256 constructors) and caused infinite memory consumption during deserialization.