feat(matplotlib): implement histogram-basic (#499)

## Summary
Implements `histogram-basic` for **matplotlib** library.

**Parent Issue:** #206
**Sub-Issue:** #490
**Base Branch:** `plot/histogram-basic`
**Attempt:** 1/3

## Implementation
- `plots/matplotlib/hist/histogram-basic/default.py`

## Details
- Uses `ax.hist()` with 30 bins for distribution visualization
- Python Blue color (#306998) with white edge lines for visual clarity
- Proper axis labels (Value, Frequency) and title with 20pt font size
- Y-axis grid lines (alpha=0.3) for readability
- Output: ~4800x2700 px image at 300 DPI with tight bounding box

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

Author: claude[bot]

plots/matplotlib/hist/histogram-basic/default.py

@@ -24,4 +24,4 @@
 ax.grid(True, alpha=0.3, axis="y")
 
 plt.tight_layout()
-plt.savefig("plot.png", dpi=300)
+plt.savefig("plot.png", dpi=300, bbox_inches="tight")