Add description for added enphase_envoy current transformer entities.

[catsmanac]

Proposed change

PR #124531 adds new entities for enphase_envoy current transformers, This PR adds the description of these to the documentation.

This PR adds description of entities voltage, current, frequency and powerfactor for each ct type if not yet available.

Type of change

• [ ] Spelling, grammar or other readability improvements (current branch).
• [ ] Adjusted missing or incorrect information in the current documentation (current branch).
• [ ] Added documentation for a new integration I'm adding to Home Assistant (next branch).
  • [ ] I've opened up a PR to add logos and icons in Brands repository.
• [x] Added documentation for a new feature I'm adding to Home Assistant (next branch).
• [ ] Removed stale or deprecated documentation.

Additional information

• Link to parent pull request in the codebase: https://github.com/home-assistant/core/pull/124531
• Link to parent pull request in the Brands repository:
• This PR fixes or closes issue: fixes #

Checklist

• [x] This PR uses the correct branch, based on one of the following:
  • I made a change to the existing documentation and used the current branch.
  • I made a change that is related to an upcoming version of Home Assistant and used the next branch.
• [x] The documentation follows the Home Assistant documentation standards.

Summary by CodeRabbit

• New Features
  • Expanded sensor metric descriptions for improved clarity in energy monitoring.
  • Introduced additional metrics for current and power factor related to production and net consumption.
• Documentation
  • Enhanced details regarding disabled sensors for battery storage, focusing on current, frequency, and power factor along with voltage.