feat: improve grouping perf in edgeless (#14442)

fix #14433 

#### PR Dependency Tree


* **PR #14442** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
  * Level-of-detail thumbnails for large images.
  * Adaptive pacing for snapping, distribution and other alignment work.
  * RAF coalescer utility to batch high-frequency updates.
  * Operation timing utility to measure synchronous work.

* **Improvements**
* Batch group/ungroup reparenting that preserves element order and
selection.
  * Coalesced panning and drag updates to reduce jitter.
* Connector/group indexing for more reliable updates, deletions and
sync.
  * Throttled viewport refresh behavior.

* **Documentation**
  * Docs added for RAF coalescer and measureOperation.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/docs/api/@blocksuite/std/gfx/functions/createRafCoalescer.md

@@ -0,0 +1,27 @@
+[**BlockSuite API Documentation**](../../../../README.md)
+
+***
+
+[BlockSuite API Documentation](../../../../README.md) / [@blocksuite/std](../../README.md) / [gfx](../README.md) / createRafCoalescer
+
+# Function: createRafCoalescer()
+
+> **createRafCoalescer**\<`T`\>(`apply`): `RafCoalescer`\<`T`\>
+
+Coalesce high-frequency updates and only process the latest payload in one frame.
+
+## Type Parameters
+
+### T
+
+`T`
+
+## Parameters
+
+### apply
+
+(`payload`) => `void`
+
+## Returns
+
+`RafCoalescer`\<`T`\>