Setup proper pip package (#2239)

[AgentsLogic]

Fixes #2239

Summary

This PR sets up pandacan as a proper pip package that includes firmware, certificates, and all necessary components to fully use the panda project.

Changes

• Add setup.py with custom build command to optionally build firmware during installation
• Add MANIFEST.in to include firmware binaries, certificates, and header files in the package distribution
• Update pyproject.toml with:
  • Proper package metadata (keywords, classifiers, URLs)
  • CLI entry points for panda-health, panda-flash, and panda-version commands
  • Package data configuration to include board files and certs
  • Move opendbc to optional dev dependencies
• Make opendbc import optional in python/__init__.py to prevent installation failures when opendbc is not available
• Convert script main functions to be callable from CLI entry points:
  • scripts/get_version.py
  • scripts/can_health.py
  • scripts/reflash_internal_panda.py

Key Features

• Package can be installed with pip install pandacan
• Firmware is optionally built during installation if ARM toolchain is available
• Falls back gracefully if firmware build fails or toolchain is missing
• CLI commands are available after installation:
  • panda-health - Monitor panda CAN health
  • panda-flash - Flash internal panda
  • panda-version - Get panda version
• All necessary files (firmware, certs, headers) are included in the package
• opendbc is now an optional dev dependency, preventing installation conflicts

Testing

The package should be sufficient to remove panda as a submodule from openpilot and add it as a normal Python dependency. This will be validated in a follow-up openpilot PR.

Notes

• The setup.py includes intelligent firmware building that:
  • Checks for ARM GCC toolchain availability
  • Runs scons to build firmware if toolchain is present
  • Continues with package build even if firmware build fails
  • Provides clear messages about firmware build status