JS Editor: add missing block coverage Phase 3 (Heap)

[zealot-zew]

This PR introduces full support for Heap blocks within the JavaScript Editor. Users can now manage dynamic lists of data directly via JavaScript, with seamless "round-trip" conversion back to visual blocks. This includes new getters for heap state and methods for manipulating stored data.

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Newly Supported Heap Blocks

The following blocks are now fully wired into the JS export/runtime and the conversion pipeline:

Data Getters (Values)

Block	JavaScript Equivalent	Description
Heap	mouse.HEAP	Returns the entire heap as a JSON string.
Heap Length	mouse.HEAPLENGTH	Returns the number of items currently in the heap.
Heap Empty?	mouse.HEAPEMPTY	Returns a boolean (true/false) if the heap is empty.

Action Blocks (Methods)

Block	JavaScript Equivalent	Description
Push	await mouse.push(value)	Adds a new value to the end of the heap.
Set Heap Entry	await mouse.setHeapEntry(index, value)	Updates or adds a value at a specific index (1–1000).
Empty Heap	await mouse.emptyHeap()	Clears all data from the turtle's heap.
Reverse Heap	await mouse.reverseHeap()	Reverses the order of items in the heap in place.

Images:

Previous Works:
PR #5834
PR #5898

[github-actions]

✅ All Jest tests passed! This PR is ready to merge.