Fix Docker image tagging for pre-release versions

The semver patterns in docker/metadata-action don't match pre-release
tags like v1.0-rc2. Add a type=match rule that extracts the version
from any v* tag so RC and other pre-release builds get proper tags.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/docker-build-trusted.yml

@@ -57,6 +57,7 @@ jobs:
             type=semver,pattern={{version}}
             type=semver,pattern={{major}}.{{minor}}
             type=semver,pattern={{major}}
+            type=match,pattern=v(.*),group=1
             type=sha
             type=raw,value=latest,enable={{is_default_branch}}