fix(cli): promote --format to global CLI callback option per spec

Add `fmt: OutputFormat` parameter to `main_callback()` in
`src/cleveragents/cli/main.py` and store the selected format in
`ctx.obj["format"]` so all subcommands can read it without needing
their own per-command `--format` flag.

Remove per-command `--format` / `fmt` parameters from `version()`,
`info()`, and `diagnostics()` commands. These commands now read the
format from `ctx.obj.get("format", OutputFormat.RICH.value)`.

The specification states: "The framework supports six distinct output
formats, selectable via the global `--format` flag." This change
aligns the implementation with the spec by making `--format` a global
option on the root `agents` command (via the Typer callback).

All six formats (json, yaml, plain, rich, table, color) are supported
via the global flag and the `-f` shorthand.

Add Behave BDD scenarios covering global `--format` flag propagation
to subcommands for all six formats. Update Robot Framework integration
tests to exercise the global `--format` flag. Update existing tests
that used per-command `--format` for version/info/diagnostics to use
the global flag instead.

ISSUES CLOSED: #2908

robot/helper_cli_formats.py

@@ -133,11 +133,99 @@ def plan_status_plain() -> None:
     print("cli-formats-plan-status-plain-ok")
 
 
+def global_format_json_version() -> None:
+    """Test global --format json propagates to version command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["--format", "json", "version"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    parsed = json.loads(result.output.strip())
+    assert isinstance(parsed, dict)
+    assert "version" in parsed
+    print("cli-global-format-json-version-ok")
+
+
+def global_format_yaml_version() -> None:
+    """Test global --format yaml propagates to version command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["--format", "yaml", "version"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    parsed = yaml.safe_load(result.output.strip())
+    assert isinstance(parsed, dict)
+    assert "version" in parsed
+    print("cli-global-format-yaml-version-ok")
+
+
+def global_format_plain_version() -> None:
+    """Test global --format plain propagates to version command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["--format", "plain", "version"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    assert "version:" in result.output
+    print("cli-global-format-plain-version-ok")
+
+
+def global_format_json_info() -> None:
+    """Test global --format json propagates to info command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["--format", "json", "info"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    parsed = json.loads(result.output.strip())
+    assert isinstance(parsed, dict)
+    print("cli-global-format-json-info-ok")
+
+
+def global_format_json_diagnostics() -> None:
+    """Test global --format json propagates to diagnostics command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["--format", "json", "diagnostics"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    parsed = json.loads(result.output.strip())
+    assert isinstance(parsed, dict)
+    print("cli-global-format-json-diagnostics-ok")
+
+
+def global_format_shorthand() -> None:
+    """Test global -f json shorthand propagates to version command."""
+    from cleveragents.cli.main import app as main_app
+
+    result = runner.invoke(main_app, ["-f", "json", "version"])
+    assert result.exit_code == 0, f"exit={result.exit_code}: {result.output}"
+    parsed = json.loads(result.output.strip())
+    assert isinstance(parsed, dict)
+    assert "version" in parsed
+    print("cli-global-format-shorthand-ok")
+
+
+def global_format_all_six() -> None:
+    """Test all six output formats work via the global --format flag."""
+    from cleveragents.cli.main import app as main_app
+
+    formats = ["json", "yaml", "plain", "rich", "table", "color"]
+    for fmt in formats:
+        result = runner.invoke(main_app, ["--format", fmt, "version"])
+        assert result.exit_code == 0, (
+            f"Format '{fmt}' failed: exit={result.exit_code}: {result.output}"
+        )
+    print("cli-global-format-all-six-ok")
+
+
 _COMMANDS = {
     "action-list-json": action_list_json,
     "action-show-yaml": action_show_yaml,
     "plan-list-json": plan_list_json,
     "plan-status-plain": plan_status_plain,
+    "global-format-json-version": global_format_json_version,
+    "global-format-yaml-version": global_format_yaml_version,
+    "global-format-plain-version": global_format_plain_version,
+    "global-format-json-info": global_format_json_info,
+    "global-format-json-diagnostics": global_format_json_diagnostics,
+    "global-format-shorthand": global_format_shorthand,
+    "global-format-all-six": global_format_all_six,
 }
 
 if __name__ == "__main__":