KCL: Convert x/y lines to use keyword arguments (#5615)

Previously, `xLine`, `xLineTo`, `yLine` and `yLineTo` used positional arguments. Now:

- `xLineTo` and `yLineTo` have been removed
- `xLine` and `yLine` both use keyword arguments:
  - `length`, optional (i.e. a relative distance along the X or Y axis)
  - `endAbsolute` optional (i.e. an absolute point along the X or Y axis)
  - `tag` optional
- Exactly one of `length` or `endAbsolute` must be given. Not both, not neither.

For example:

```
// Old way
|> xLine(6.04, %)
|> yLineTo(20, %, $base)

// New way
|> xLine(length = 6.04)
|> yLine(endAbsolute = 20, tag = $base)
```

This also improves some of the general-purpose keyword arguments code in modeling app's TS codebase.

e2e/playwright/test-network-and-connection-issues.spec.ts

@@ -122,7 +122,7 @@ test.describe('Test network and connection issues', () => {
 
       await expect(page.locator('.cm-content'))
         .toHaveText(`sketch001 = startSketchOn('XZ')profile001 = startProfileAt(${commonPoints.startAt}, sketch001)
-      |> xLine(${commonPoints.num1}, %)`)
+      |> xLine(length = ${commonPoints.num1})`)
 
       // Expect the network to be up
       await expect(networkToggle).toContainText('Connected')
@@ -215,7 +215,7 @@ test.describe('Test network and connection issues', () => {
       await expect.poll(u.normalisedEditorCode)
         .toBe(`sketch001 = startSketchOn('XZ')
 profile001 = startProfileAt([12.34, -12.34], sketch001)
-  |> xLine(12.34, %)
+  |> xLine(length = 12.34)
   |> line(end = [-12.34, 12.34])
 
 `)
@@ -225,9 +225,9 @@ profile001 = startProfileAt([12.34, -12.34], sketch001)
       await expect.poll(u.normalisedEditorCode)
         .toBe(`sketch001 = startSketchOn('XZ')
 profile001 = startProfileAt([12.34, -12.34], sketch001)
-  |> xLine(12.34, %)
+  |> xLine(length = 12.34)
   |> line(end = [-12.34, 12.34])
-  |> xLine(-12.34, %)
+  |> xLine(length = -12.34)
 
 `)