Add version command with comprehensive unit tests and build integration

- Implement llama version command with table and JSON output formats
- Add build-time git information capture via scripts/generate_build_info.py
- Include comprehensive unit test suite (test_version.py, test_version_simple.py, test_version_integration.py)
- Add build system integration with custom setup.py command
- Update .gitignore to exclude generated build info file

Features:
- Display Llama Stack and client versions
- Show Python version and build information (git commit, date, branch, tag)
- Optional component/provider listing organized by API
- Support for both table and JSON output formats
- Build-time capture of git metadata for version tracking

Testing:
- 8 unit tests covering all functionality
- Integration tests for CLI execution
- Simple dependency-free validation tests
- Documentation for test suite and build process

Signed-off-by: Akram Ben Aissi <akram.benaissi@gmail.com>

llama_stack/cli/llama.py

@@ -11,6 +11,7 @@ from .model import ModelParser
 from .stack import StackParser
 from .stack.utils import print_subcommand_description
 from .verify_download import VerifyDownload
+from .version import VersionCommand
 
 
 class LlamaCLIParser:
@@ -34,6 +35,7 @@ class LlamaCLIParser:
         StackParser.create(subparsers)
         Download.create(subparsers)
         VerifyDownload.create(subparsers)
+        VersionCommand.create(subparsers)
 
         print_subcommand_description(self.parser, subparsers)