feat(cli): Enhance test command functionality and add new status features

- Refactored the HandleTestCommand to support subcommands: status, list, and results.
- Implemented HandleTestStatusCommand to fetch and display the status of a test by ID.
- Added HandleTestListCommand to list tests with optional filters for category and status.
- Created HandleTestResultsCommand to retrieve detailed results for a specific test execution.
- Introduced new structures for test status details, test summaries, and results.
- Updated GuiAutomationClient to support gRPC calls for fetching test status and results.
- Enhanced the ModernCLI to reflect new command usage for test operations.
- Added JSON and YAML formatting for test results output.

src/cli/modern_cli.cc

@@ -60,7 +60,11 @@ void ModernCLI::SetupCommands() {
     commands_["agent"] = {
       .name = "agent",
       .description = "Interact with the AI agent",
-      .usage = "z3ed agent <run|plan|diff|test|learn|commit|revert|describe> [options]\n"
+      .usage = "z3ed agent <run|plan|diff|test|list|learn|commit|revert|describe> [options]\n"
+               "  test run:     --prompt \"<description>\" [--host <host>] [--port <port>] [--timeout <sec>]\n"
+               "  test status:  status --test-id <id> [--follow] [--host <host>] [--port <port>]\n"
+               "  test list:    list [--category <name>] [--status <state>] [--limit <n>] [--host <host>] [--port <port>]\n"
+               "  test results: results --test-id <id> [--include-logs] [--format yaml|json] [--host <host>] [--port <port>]\n"
                "  describe options: [--resource <name>] [--format json|yaml] [--output <path>]\n"
                "                     [--version <value>] [--last-updated <date>]",
       .handler = [this](const std::vector<std::string>& args) -> absl::Status {