Feature: Enhance button.Base text config to support VDOM cn arrays

This ticket documents a significant enhancement to Neo.button.Base, allowing its text config to accept a VDOM cn (children) array in addition to a standard string. This provides a cleaner, more secure, and more performant way to define complex button content.

Problem

Previously, creating a button with mixed content (e.g., an icon or styled text next to plain text) required workarounds. A temporary solution involved parsing the text string for HTML, which was convenient but had several drawbacks:

• It was architecturally inconsistent with the framework's VDOM-first approach.
• It relied on setting innerHTML, which is a potential Cross-Site Scripting (XSS) security risk.
• It was inefficient, as any change required replacing the entire button content instead of allowing for granular updates.

Solution

The afterSetText method in src/button/Base.mjs has been updated to intelligently handle its value:

• If the value is a String, it is assigned to the textNode.text property as before.
• If the value is an Array, it is treated as a VDOM cn array and assigned to the textNode.cn property.

This allows developers to define rich button content using a standard VDOM structure.

Example

// Before (using an HTML string hack, plus regression issue in v10)
{
    handler: 'onSeriesButtonClick',
    series : 'active',
    text   : '<span style="color: #64b5f6">●</span> Active'
}

// After (using a clean VDOM array)
{
    handler: 'onSeriesButtonClick',
    series : 'active',
    text   : [{tag: 'span', style: {color: '#64b5f6'}, text: '●'}, {vtype: 'text', text: ' Active'}]
}

Key Advantages

1. Cleaner & More Consistent API: This change aligns button.Base with the rest of the framework. Developers can now compose button content using the same declarative VDOM structure they use everywhere else, making the API more predictable and idiomatic.

2. XSS Secure by Default: By processing a VDOM structure instead of an HTML string, the framework builds the DOM programmatically. This completely avoids the use of innerHTML for the button's content, eliminating the risk of XSS attacks from malicious strings.

3. Enables Granular Delta Updates: When the button's content is part of the VDOM tree, the framework's diffing engine can perform highly efficient delta updates. If only one part of the button's content changes (e.g., a number in a label), only that specific text node will be updated in the DOM, rather than re-rendering the entire button's content. This significantly improves rendering performance for dynamic buttons.