Fix order total for partial capture

[Serfe-com]

Fixes #2799

This PR addresses two issues related to order status updates and partial capture:

1. Prevents changes to the order total when updating the order status during a partial capture.
2. Adds a refund entry with the message "Partial Capture" to accurately reflect partial refunds in line with Stripe's charge details.

Changes proposed in this Pull Request:

• Webhook process_webhook_capture:

  • Prevents modification of the order total during status changes.
  • Introduces a partial refund entry to ensure the order total remains unaffected by status changes.
  • Add an status change from "on_hold" to "processing"

• Order Notes:

  • Adjusts the number representation to a float with two decimal places for consistency and clarity.

Testing instructions

⚠️ Note: you need to have webhooks working in order to receive the capture webhook from Stripe.

1. Enable auth and capture from the Stripe settings.

   • WooCommerce → Settings → Payments → Stripe → Settings (Transaction preferences)

2. Purchase any product.

3. Go to the Stripe Dashboard and view the transaction.
   

4. Click the capture button and enter an amount below the full total. eg $15 ⇒ $5
   

5. View the order in WooCommerce with the following information:

   • It's on processing status
   • The order has a partial refund with the no-capture amount
   • The order total doesn't change

6. If you change the order status to any status, you will no see any total change

---

• Covered with tests (or have a good reason not to test in description ☝️)
• Added changelog entry in both changelog.txt and readme.txt (or does not apply)
• Tested on mobile (or does not apply)

Post merge

• Added testing instructions to the Release Testing Instructions wiki page (or does not apply)
• Added the needs docs label (or does not apply)
• Included this PR in the Release Thread scope (or does not apply)