Fix production CI deployment and simplify tag pipeline

- Change prod namespace from orch-prod-namespace to orch-namespace
- Skip all build/test/scan jobs on tag pipelines (image already built on main)
- Tag pipelines now only run deploy_prod and smoke_test_prod

CHANGELOG.md

@@ -6,6 +6,11 @@ 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).
 
 ## [Unreleased]
+### Changed
+- Simplified tag pipeline to only run deploy and smoke tests (image already built on main) (#54)
+
+### Fixed
+- Fixed production CI deployment namespace to use correct `orch-namespace` (#54)
 
 ## [0.5.0] - 2026-01-23
 ### Added