docs: Use a plain semver line for fork releases

CHANGELOG.md

@@ -5,10 +5,13 @@ https://github.com/dermotduffy/advanced-camera-card/releases
 
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
-Fork versions carry the upstream version they are built from plus a `+flan.N`
-build identifier.
+Fork versions are this fork's own semver line; each entry names the upstream
+release it is built from. A `+`-suffixed or pre-release tag was avoided
+deliberately: HACS hides pre-releases unless beta versions are enabled.
 
-## [8.0.2+flan.1] - 2026-09-04
+## [8.1.0] - 2026-09-04
+
+Built from upstream [v8.0.2](https://github.com/dermotduffy/advanced-camera-card/releases/tag/v8.0.2).
 
 ### Added
 

FORK.md

@@ -35,6 +35,13 @@ An explicit severity chosen in the media filter drawer still wins, so the
 interactive filter keeps working. Unset means all severities, so a config that
 does not mention `severities` behaves exactly as upstream does.
 
+## Versioning
+
+This fork has its own semver line, starting at `8.1.0` (upstream `v8.0.2` plus
+the feature above). Tags are plain semver — HACS hides pre-release versions
+unless the user has enabled beta versions, so a `-flan.N` style tag would make
+the release invisible to HACS.
+
 ## Keeping up with upstream
 
 ```bash