fix(theme-chalk): [form] remove default width of Input in inline form

[tolking]

Revert #12897

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Description

🤖 Generated by Copilot at 9f36216

This pull request enhances the documentation and code quality of the Form and Input components. It updates the type and comment of some Form props, adds a FAQ section to the Input documentation, shows how to use CSS variables to control the input width in the inline form example, and removes an unused style rule for the ElInput component.

Related Issue

Fixes #___.

Explanation of Changes

🤖 Generated by Copilot at 9f36216

• Remove outdated comment about ElInput width issue in inline form documentation (link)
• Update type annotation of model and scroll-into-view-options props of Form component to use Record<string, any> instead of object (link)
• Fix typo in closing tag of details element in type declarations documentation (link)
• Add FAQ section to Input component documentation explaining how to fix width expansion when using clearable prop (link)
• Add style block to inline form example code demonstrating how to control ElInput width using CSS variables (link)
• Remove redundant style rule for ElInput width in form.scss (link)

[github-actions]

[github-actions]

🧪 Playground Preview: https://element-plus.run/?pr=13375
Please comment the example via this playground if needed.

[jeff-fe]

👍🏻