feat: autoStop, onThreshold callbacks, and progress label

[franverona]

Overview

Three related enhancements to improve progress control and visual feedback.

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autoStop

A new boolean option that automatically calls stop() when setprogress(100) is reached, removing boilerplate users currently wire up manually.

Proposed API:

// Vanilla
Loadgo.init(el, { autoStop: true })

// jQuery
$('#logo').loadgo({ autoStop: true })

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onThreshold

A new option that fires callbacks when progress crosses specific threshold values. Useful for multi-stage loading UIs (e.g. showing a message at 50%, unlocking a button at 100%).

Thresholds should only fire once per crossing (not on every setprogress call while above the value).

Proposed API:

Loadgo.init(el, {
  onThreshold: {
    50: () => console.log('halfway there'),
    75: () => console.log('almost done'),
    100: () => console.log('complete'),
  }
})

---

Progress label

A new option to display the current progress percentage as text inside the overlay. Should support a configurable template string.

Proposed API:

Loadgo.init(el, {
  showLabel: true,
  labelTemplate: '{progress}%',  // default
})

The label element should be styled to be centered over the overlay and excluded when filter mode is active (since there is no overlay in that case).

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Notes

• All three options should be supported in both loadgo.js (jQuery) and loadgo-vanilla.js.
• onThreshold composes naturally with the custom events work currently in progress.
• autoStop and the 100 threshold in onThreshold are complementary but independent — both can be used together.