feat(plotly): implement histogram-basic (#466)

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

**Parent Issue:** #206
**Sub-Issue:** #426
**Base Branch:** `plot/histogram-basic`
**Attempt:** 1/3

## Implementation
- `plots/plotly/histogram/histogram-basic/default.py`

## Features
- Basic histogram visualization using `go.Histogram`
- Sample data: 500 values from normal distribution (mean=100, std=15)
- Python Blue color palette (#306998) with white bar outlines
- Proper typography for 4800x2700 output (40pt titles, 32pt labels)
- Clean `plotly_white` template with subtle grid styling
- 5% bar gap for visual clarity

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

Author: claude[bot]

plots/plotly/histogram/histogram-basic/default.py

@@ -9,24 +9,21 @@
 
 # Data
 np.random.seed(42)
-values = np.random.normal(100, 15, 500)
+values = np.random.normal(100, 15, 500)  # 500 values, mean=100, std=15
 
 # Create figure
 fig = go.Figure()
-fig.add_trace(
-    go.Histogram(
-        x=values, marker_color="#306998", opacity=0.85, hovertemplate="Range: %{x}<br>Count: %{y}<extra></extra>"
-    )
-)
+fig.add_trace(go.Histogram(x=values, marker={"color": "#306998", "line": {"color": "white", "width": 1}}, opacity=0.85))
 
 # Layout
 fig.update_layout(
     title={"text": "Basic Histogram", "font": {"size": 40}, "x": 0.5, "xanchor": "center"},
-    xaxis_title={"text": "Value", "font": {"size": 40}},
-    yaxis_title={"text": "Frequency", "font": {"size": 40}},
+    xaxis_title="Value",
+    yaxis_title="Frequency",
     template="plotly_white",
-    xaxis={"tickfont": {"size": 32}, "showgrid": True, "gridcolor": "rgba(0,0,0,0.1)"},
-    yaxis={"tickfont": {"size": 32}, "showgrid": True, "gridcolor": "rgba(0,0,0,0.1)"},
+    font={"size": 32},
+    xaxis={"title_font": {"size": 40}, "tickfont": {"size": 32}, "showgrid": True, "gridcolor": "rgba(0,0,0,0.1)"},
+    yaxis={"title_font": {"size": 40}, "tickfont": {"size": 32}, "showgrid": True, "gridcolor": "rgba(0,0,0,0.1)"},
     bargap=0.05,
 )