chore: pin release to 6.3.0-beta.9 (keep off major; breaking change ships in beta)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: bokelley

.release-please-manifest.json

@@ -1,3 +1,3 @@
 {
-  ".": "7.0.0-beta.8"
+  ".": "6.3.0-beta.9"
 }

CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
 
-## [7.0.0-beta.8](https://github.com/adcontextprotocol/adcp-client-python/compare/v6.3.0-beta.8...v7.0.0-beta.8) (2026-06-07)
+## [6.3.0-beta.9](https://github.com/adcontextprotocol/adcp-client-python/compare/v6.3.0-beta.8...v6.3.0-beta.9) (2026-06-07)
 
 
 ### ⚠ BREAKING CHANGES

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "adcp"
-version = "7.0.0b8"
+version = "6.3.0b9"
 description = "Official Python client for the Ad Context Protocol (AdCP)"
 authors = [
     {name = "AdCP Community", email = "maintainers@adcontextprotocol.org"}