feat: add local config commands (list versions, download XML)

[cdot65]

Overview

Add scm local command group for listing device configuration versions and downloading config files as XML. Wraps the new client.local_config service from SDK 0.13.0.

Context

SDK 0.13.0 adds client.local_config with:

• List versions: Get configuration version history for a device
• Download config: Download a specific config version as raw XML (uses raw_response for binary download)
• Pydantic models for local config version data

Dependencies

• Requires feat: upgrade pan-scm-sdk to ^0.13.0 and add region support #212 (SDK 0.13.0 upgrade + region support) (SDK 0.13.0 upgrade + region support) to land first

Design Decisions (from brainstorming session 2026-04-16)

1. Top-level command group: scm local list and scm local download (not nested under existing groups)
2. Download output: Default to stdout, --output <path> writes to file
3. Follows existing CLI patterns: Typer app, @handle_command_errors, consistent option naming

Scope

• In scope:
  • New command module: src/scm_cli/commands/local.py
  • Subcommands: scm local list --device <name> and scm local download --device <name> --version <id> [--output config.xml]
  • SDK client methods in sdk_client.py: list_local_config_versions(), download_local_config()
  • Validator models in validators.py (if needed for input validation)
  • Mock mode support with realistic sample data
  • Register in main.py as top-level command group
  • Tests: tests/test_local_commands.py
  • Documentation: docs/cli/local/ pages
  • Update mkdocs.yml nav
• Out of scope:
  • Device operations commands (see separate issue)
  • Config diff/comparison features (future enhancement)

CLI Interface

# List config versions for a device
scm local list --device fw-01

# Download a specific version to stdout
scm local download --device fw-01 --version 42

# Download to a file
scm local download --device fw-01 --version 42 --output fw-01-v42.xml

# Mock mode
scm local list --device fw-01 --mock

Acceptance Criteria

• src/scm_cli/commands/local.py exists with list and download subcommands
• scm local list --device <name> shows config versions in table format
• scm local download --device <name> --version <id> outputs XML to stdout
• scm local download --output <path> writes XML to file
• SDK client methods added with proper error handling
• Mock mode returns realistic sample config version data
• Unit tests in tests/test_local_commands.py covering list, download-to-stdout, download-to-file, error cases
• Documentation pages created and linked in mkdocs.yml
• make quality passes
• Module follows style guide (191-char separators, Google docstrings, section organization)

Implementation Notes

• Download uses raw_response=True in Scm.request() — the response body is raw XML bytes
• For stdout output, decode XML as UTF-8; for file output, write binary
• Table columns for list: version number, date, author/source, description (based on SDK model fields)
• Follow commands/jobs.py as a pattern reference — similar "list + show detail" structure