fix: Show unlimited approval amount in readonly mode

[usame-algan]

What it solves

Part of #2067

How this PR fixes it

• Extracts readonly part from ApprovalEditorForm
• Displays Unlimited approvals correctly in readonly mode

How to test it

1. Open a Safe with queued approvals (unlimited and limited)
2. Observe the values are displayed correctly

ToDos

• Write tests for ApprovalEditor and the new components

Screenshots

Checklist

• I've tested the branch on mobile 📱
• I've documented how it affects the analytics (if at all) 📊
• I've written a unit/e2e test for it (if applicable) 🧑‍💻

[github-actions]

Branch preview

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https://fix_approval_amount--walletweb.review-wallet-web.5afe.dev

[github-actions]

ESLint Summary View Full Report

Annotations are provided inline on the Files Changed tab. You can also see all annotations that were generated on the annotations page.

Type	Occurrences	Fixable
Errors	0	0
Warnings	0	0
Ignored	0	N/A

• Result: ✅ success
• Annotations: 0 total

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