Add domain-scenario Gherkin tags to all A2A, session, and CLI feature
files (30 files) so tests can be filtered individually via behave.
- 8 A2A feature files: @a2a tag
- 7 session feature files: @session tag
- 15 CLI feature files: @cli tag
ISSUES CLOSED: #9124
Add structured data builders and Rich renderers for version, info, and
diagnostics commands. Support --format rich/plain/json/yaml output parity
and --check flag for diagnostics (exits non-zero on errors).
Includes Behave scenarios, Robot smoke tests, ASV benchmarks, and updates
existing tests to match the new Rich panel output format.
HAL9000
khyari hamza
freemo
