feat(editor): LaserPointer based freedraw (#11507)

Introduces constant width freedraw mode, keeping the original variable mode as default.

---------

Signed-off-by: Mark Tolmacs <mark@lazycat.hu>
Co-authored-by: dwelle <5153846+dwelle@users.noreply.github.com>

packages/laser-pointer/README.md

@@ -0,0 +1,23 @@
+# Laser Pointer
+
+## Usage
+
+    import { LaserPointer } from '@excalidraw/laser-pointer'
+
+    const stroke = new LaserPointer(options)
+
+    stroke.addPoint([100, 200, 1])
+    stroke.close()
+
+    const outline = stroke.getStrokeOutline()
+
+## Options
+
+| Property | Type | Default | Description |
+| --- | --- | --- | --- |
+| `size` | `number` | `2` | Radius of the stroke. |
+| `streamline` | `number` | `0.42` | Interpolate input points to reduce jitter. |
+| `simplify` | `number` | `0.1` | Reduce stroke size by sacrificing precision. |
+| `simplifyPhase` | `"input" \| "output" \| "tail" ` | `"output"` | Decides when the simplification algorithm should be applied. |
+| `sizeMapping` | `(details: SizeMappingDetails) => number` | `() => 1` | Maps each point to a value between `0.0` and `1.0`. |
+| `keepHead` | `boolean` | `false` | Whether size mapping should influence the head of the stroke. |