Add ChargeHQ export plugin

[rianbk]

Summary

• Add new export plugin for ChargeHQ Push API
• Enables EV charging optimization based on solar production
• Supports both grid-tied (SG*) and hybrid (SH*) inverters
• Configurable register mappings for different setups

Features

• Pushes production, consumption, and net import data to ChargeHQ
• Battery support for hybrid inverters (SOC, charge/discharge power)
• Rate limiting (default 60s) per ChargeHQ API guidelines
• Automatic unit conversion (W → kW, % → decimal)

Configuration Example

- name: chargehq
  enabled: True
  api_key: "your-api-key"
  # For SG* models with smart meter:
  register_consumption: load_power
  register_net_import: meter_power
  invert_net_import: False

Testing

Tested with SG8K-D grid-tied inverter with smart meter over multiple polling cycles.