Docs: Improve LuxPower Freeze Charge Exit Automation: Fix Trigger/Condition Logic to Handle Predbat Restarts

[brickatius]

This PR updates the LuxPower Freeze Charge Exit automation in the LuxPower section of the Inverter Setup documentation to ensure it correctly disables freeze‑charge automations in an edge case where Predbat is restarted or updated whilst predbat_status is Freeze charging.

Background
When Predbat enters Freeze charging, the freeze_charge_guard boolean is set to on.
However, if Predbat is restarted or updated while in this state, its next reported status may no longer be “Freeze charging”. In this scenario, the existing automation does not trigger, because it relied on a state transition from “Freeze charging”.

As a result:

• The Freeze Charge Exit automation does not run
• Freeze‑charge automations remain incorrectly enabled
• Users may remain stuck in freeze‑charge mode until manual intervention

Fix
This PR updates the automation to trigger on any Predbat status change, and adds conditions to detect when:

• freeze_charge_guard is still on, and
• The new Predbat status is valid, not an error/warning, and not “Freeze charging”

Recommended Update for Existing Users
Users with an existing LuxPower freeze‑charge setup should update their Freeze Charge Exit automation to use the following trigger and conditions:

triggers:
  - entity_id: predbat.status
    trigger: state

conditions:
  - condition: state
    entity_id: input_boolean.freeze_charge_guard
    state: "on"

  - condition: template
    value_template: |
      {% set new = trigger.to_state.state | default('') %}
      {{
        new not in ['unknown','unavailable'] and
        not new.startswith('Warn:') and
        not new.startswith('Error:') and
        'Freeze charging' not in new
      }}

This ensures the exit automation fires correctly even after a Predbat restart or update.

Note
This change affects only the Home Assistant automation logic.
It does not require any modification to Predbat core, LuxPower integration code, or inverter configuration.