feat(tools): add can_tester PC-side debugging tool

[Yusuf-Serdar]

Summary

Ports tools/can_tester/ from PicoLowLevel, updated for the STM32LowLevel CAN FD protocol.

Closes #41

Changes

Protocol updates

• CAN FD: fd=True, bitrate_switch=True on all sent frames; --data-bitrate / -D arg (default 2 Mbit/s) added to CLI and web dashboard
• Bitrate: default 125 kbps → 1 Mbit/s arbitration + 2 Mbit/s data (matches FDCAN2 config)
• MsgType: removed DATA_PITCH = 0x04 (not in communication.h); enum now has exactly 44 entries, all verified against Inc/communication.h
• Modules: MK2_MOD1 / MOD2 / MOD3 only — MK1 variants removed from CLI choices and web dashboard dropdown

header_parser

• Updated _DEFAULT_INCLUDE_DIR to point to STM32LowLevel/Inc
• Added #if A == B / #elif A == B regex support for MODULE_DEFINE == MK2_MOD1 style guards
• Added #define NAME IDENTIFIER resolution (handles #define CAN_ID MK2_MOD1)
• Added _MODULE_ADDRESSES map and predefined_values injection for parse_mod_config()

Bug fix

• cli.py _handle_send: parts[2] → args[1] (wrong variable used for "permanent" flag check)

Validation

• test_dry.py runs without hardware; all tests pass:
  • CAN ID encode/decode round-trip
  • Payload codec (MOTOR_SETPOINT, ARM_PITCH, RESET_ARM)
  • Module config: CAN_ID 0x21/0x22/0x23 verified per variant
  • MsgType count == 44
  • 7 test sequences importable