feat(components): [tabs] add addIcon slot

[btea]

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Description

🤖 Generated by Copilot at f6cca1c

Added a new addIcon slot to the Tabs component and updated the documentation accordingly. This slot enables users to customize the appearance of the add button for editable tabs.

Related Issue

feat #11795 .

Explanation of Changes

🤖 Generated by Copilot at f6cca1c

• Add a new slot addIcon to the Tabs component to allow customizing the icon of the add button for editable tabs (link, link, link)
• Render the addIcon slot in the tabs.tsx file if it is provided, or fall back to the default plus icon (link)

[github-actions]

[github-actions]

🧪 Playground Preview: https://element-plus.run/?pr=12970
Please comment the example via this playground if needed.

[ryuhangyeong]

Personally, I think the function is useful, but I think it would be better to get a prop rather than a slot.

How about this?

[btea]

Personally, I think the function is useful, but I think it would be better to get a prop rather than a slot.

How about this?

Do you mean to add a prop similar to actionIcon, and then the default value is Plus?

This seems to be possible, but in this case, if the user wants to customize the element structure, it seems to be more troublesome. 🤔

[ryuhangyeong]

Personally, I think the function is useful, but I think it would be better to get a prop rather than a slot.

How about this?

Do you mean to add a prop similar to actionIcon, and then the default value is Plus?

This seems to be possible, but in this case, if the user wants to customize the element structure, it seems to be more troublesome. 🤔

my opinion

From the name addicon, I already got the impression that only icons are available.

And since the area is not long, I think it is difficult to use it as a custom area.

I'd love to hear more people's opinions!

[btea]

From the name addicon, I already got the impression that only icons are available.

I just gave an example, maybe you can customize the text, such as Add. However, as you said, the area is not long, maybe it is better to only support icons. 🤔