feat(plotly): implement line-filled (#2667)

## Implementation: `line-filled` - plotly

Implements the **plotly** version of `line-filled`.

**File:** `plots/line-filled/implementations/plotly.py`

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:robot: *[impl-generate
workflow](https://github.com/MarkusNeusinger/pyplots/actions/runs/20595332881)*

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

Author: github-actions[bot]

plots/line-filled/metadata/plotly.yaml

@@ -0,0 +1,19 @@
+# Per-library metadata for plotly implementation of line-filled
+# Auto-generated by impl-generate.yml
+
+library: plotly
+specification_id: line-filled
+created: '2025-12-30T11:22:43Z'
+updated: '2025-12-30T11:22:43Z'
+generated_by: claude-opus-4-5-20251101
+workflow_run: 20595332881
+issue: 0
+python_version: 3.13.11
+library_version: 6.5.0
+preview_url: https://storage.googleapis.com/pyplots-images/plots/line-filled/plotly/plot.png
+preview_thumb: https://storage.googleapis.com/pyplots-images/plots/line-filled/plotly/plot_thumb.png
+preview_html: https://storage.googleapis.com/pyplots-images/plots/line-filled/plotly/plot.html
+quality_score: null
+review:
+  strengths: []
+  weaknesses: []