feat(highcharts): implement scatter-basic (#1327)

## Implementation: `scatter-basic` - highcharts

Implements the **highcharts** version of `scatter-basic`.

**File:** `plots/scatter-basic/implementations/highcharts.py`

---
:robot: *[impl-generate
workflow](https://github.com/MarkusNeusinger/pyplots/actions/runs/20446960278)*

---------

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Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: github-actions[bot]

plots/scatter-basic/implementations/highcharts.py

@@ -1,7 +1,7 @@
 """ pyplots.ai
 scatter-basic: Basic Scatter Plot
-Library: highcharts 1.10.3 | Python 3.13.11
-Quality: 100/100 | Created: 2025-12-13
+Library: highcharts unknown | Python 3.13.11
+Quality: 92/100 | Created: 2025-12-22
 """
 
 import tempfile

plots/scatter-basic/metadata/highcharts.yaml

@@ -1,17 +1,30 @@
 library: highcharts
 specification_id: scatter-basic
-created: 2025-12-13 23:14:24+00:00
-updated: 2025-12-13 23:14:24+00:00
+created: '2025-12-22T23:43:32Z'
+updated: '2025-12-23T00:06:43Z'
 generated_by: claude-opus-4-5-20251101
-workflow_run: 20199223560
-issue: 611
+workflow_run: 20446960278
+issue: 0
 python_version: 3.13.11
-library_version: 1.10.3
+library_version: unknown
 preview_url: https://storage.googleapis.com/pyplots-images/plots/scatter-basic/highcharts/plot.png
 preview_thumb: https://storage.googleapis.com/pyplots-images/plots/scatter-basic/highcharts/plot_thumb.png
 preview_html: https://storage.googleapis.com/pyplots-images/plots/scatter-basic/highcharts/plot.html
-quality_score: 100
+quality_score: 92
 review:
-  strengths: []
-  weaknesses: []
-  improvements: []
+  strengths:
+  - Excellent text sizing scaled appropriately for 4800x2700 resolution (72px title,
+    48px axis titles, 36px labels)
+  - Clean implementation following library rules with inline Highcharts JS for headless
+    Chrome compatibility
+  - Proper use of Python Blue color with transparency (rgba 0.7) for overlapping point
+    visibility
+  - Correct title format following the spec-id · library · pyplots.ai convention
+  - Both PNG and interactive HTML outputs generated
+  - Subtle dashed grid lines enhance readability without distraction
+  weaknesses:
+  - Axis labels are generic (X Value, Y Value) rather than contextual with units
+  - Marker radius (18) could be slightly smaller for better distinction between nearby
+    points
+  - Does not leverage Highcharts tooltip/hover interactivity features visible in the
+    static image