feat(seaborn): implement area-mountain-panorama (#5369)

## Implementation: `area-mountain-panorama` - python/seaborn

Implements the **python/seaborn** version of `area-mountain-panorama`.

**File:**
`plots/area-mountain-panorama/implementations/python/seaborn.py`

**Parent Issue:** #5365

---
:robot: *[impl-generate
workflow](https://github.com/MarkusNeusinger/anyplot/actions/runs/24918698887)*

---------

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

Author: github-actions[bot]

plots/area-mountain-panorama/implementations/python/seaborn.py

@@ -0,0 +1,177 @@
+""" anyplot.ai
+area-mountain-panorama: Mountain Panorama Profile with Labeled Peaks
+Library: seaborn 0.13.2 | Python 3.14.4
+Quality: 88/100 | Created: 2026-04-25
+"""
+
+import os
+
+import matplotlib.pyplot as plt
+import numpy as np
+import pandas as pd
+import seaborn as sns
+
+
+# Theme tokens
+THEME = os.getenv("ANYPLOT_THEME", "light")
+PAGE_BG = "#FAF8F1" if THEME == "light" else "#1A1A17"
+ELEVATED_BG = "#FFFDF6" if THEME == "light" else "#242420"
+INK = "#1A1A17" if THEME == "light" else "#F0EFE8"
+INK_SOFT = "#4A4A44" if THEME == "light" else "#B8B7B0"
+INK_MUTED = "#6B6A63" if THEME == "light" else "#A8A79F"
+BRAND = "#009E73"
+
+sns.set_theme(
+    style="ticks",
+    rc={
+        "figure.facecolor": PAGE_BG,
+        "axes.facecolor": PAGE_BG,
+        "axes.edgecolor": INK_SOFT,
+        "axes.labelcolor": INK,
+        "text.color": INK,
+        "xtick.color": INK_SOFT,
+        "ytick.color": INK_SOFT,
+        "grid.color": INK,
+        "grid.alpha": 0.10,
+    },
+)
+
+# Data — Wallis (Valais, Switzerland) panorama from Gornergrat, west → east sweep.
+# `sigma` is the angular half-width that shapes how broad each summit reads on
+# the silhouette: smaller = sharper, more iconic profile.
+peaks = pd.DataFrame(
+    [
+        {"name": "Weisshorn", "angle_deg": 10.0, "elevation_m": 4506, "sigma": 4.6},
+        {"name": "Zinalrothorn", "angle_deg": 22.0, "elevation_m": 4221, "sigma": 4.2},
+        {"name": "Ober Gabelhorn", "angle_deg": 32.0, "elevation_m": 4063, "sigma": 5.4},
+        {"name": "Dent Blanche", "angle_deg": 44.0, "elevation_m": 4358, "sigma": 4.6},
+        {"name": "Matterhorn", "angle_deg": 62.0, "elevation_m": 4478, "sigma": 3.0},
+        {"name": "Breithorn", "angle_deg": 82.0, "elevation_m": 4164, "sigma": 7.0},
+        {"name": "Pollux", "angle_deg": 92.0, "elevation_m": 4092, "sigma": 3.6},
+        {"name": "Castor", "angle_deg": 99.0, "elevation_m": 4223, "sigma": 3.6},
+        {"name": "Liskamm", "angle_deg": 110.0, "elevation_m": 4527, "sigma": 6.5},
+        {"name": "Dufourspitze", "angle_deg": 124.0, "elevation_m": 4634, "sigma": 5.2},
+        {"name": "Strahlhorn", "angle_deg": 142.0, "elevation_m": 4190, "sigma": 5.0},
+        {"name": "Rimpfischhorn", "angle_deg": 152.0, "elevation_m": 4199, "sigma": 4.4},
+        {"name": "Allalinhorn", "angle_deg": 161.0, "elevation_m": 4027, "sigma": 5.2},
+        {"name": "Alphubel", "angle_deg": 171.0, "elevation_m": 4206, "sigma": 4.6},
+        {"name": "Täschhorn", "angle_deg": 181.0, "elevation_m": 4491, "sigma": 3.6},
+        {"name": "Dom", "angle_deg": 191.0, "elevation_m": 4545, "sigma": 3.4},
+    ]
+)
+
+# Build the skyline as the upper envelope of per-peak Gaussian bumps over a
+# slowly undulating valley floor. This produces distinct peak shapes
+# (sharper for iconic summits, broader for massif shoulders) instead of the
+# uniform scallop pattern a global spline would give.
+np.random.seed(42)
+sample_angles = np.linspace(-5.0, 205.0, 1800)
+
+valley_floor = 2950 + 90 * np.sin(sample_angles * np.pi / 95.0 + 0.4) + 55 * np.cos(sample_angles * np.pi / 47.0 + 1.1)
+
+ridge = np.copy(valley_floor)
+for _, row in peaks.iterrows():
+    floor_at_peak = valley_floor[np.argmin(np.abs(sample_angles - row["angle_deg"]))]
+    bump_height = row["elevation_m"] - floor_at_peak
+    bump = bump_height * np.exp(-0.5 * ((sample_angles - row["angle_deg"]) / row["sigma"]) ** 2)
+    ridge = np.maximum(ridge, valley_floor + bump)
+
+# High-frequency rocky texture; tapered so edges blend into the valley floor
+texture = (
+    35 * np.sin(sample_angles * 1.7 + 0.3)
+    + 22 * np.sin(sample_angles * 3.1 + 1.7)
+    + np.random.normal(0, 14, size=sample_angles.shape)
+)
+edge_taper = np.clip((sample_angles - 0) / 6, 0, 1) * np.clip((200 - sample_angles) / 6, 0, 1)
+ridge = ridge + texture * edge_taper
+
+skyline = pd.DataFrame({"angle_deg": sample_angles, "elevation_m": ridge})
+
+# Plot
+fig, ax = plt.subplots(figsize=(16, 9), facecolor=PAGE_BG)
+ax.set_facecolor(PAGE_BG)
+
+Y_FLOOR = 2500
+LABEL_BASE_Y = 5150
+LABEL_STAGGER = 360
+
+# Filled silhouette
+ax.fill_between(skyline["angle_deg"], skyline["elevation_m"], Y_FLOOR, color=BRAND, alpha=1.0, linewidth=0, zorder=2)
+sns.lineplot(data=skyline, x="angle_deg", y="elevation_m", color=BRAND, linewidth=1.6, ax=ax, legend=False)
+
+# Peak labels with leader lines, alternating heights to avoid overlap
+for i, row in peaks.iterrows():
+    is_anchor = row["name"] == "Matterhorn"
+    label_y = LABEL_BASE_Y + (LABEL_STAGGER if i % 2 == 0 else 0)
+    leader_top = label_y - 80
+
+    ax.plot(
+        [row["angle_deg"], row["angle_deg"]],
+        [row["elevation_m"], leader_top],
+        color=INK_SOFT,
+        linewidth=1.0,
+        alpha=0.65,
+        zorder=3,
+    )
+
+    ax.text(
+        row["angle_deg"],
+        label_y,
+        row["name"],
+        fontsize=15 if is_anchor else 13,
+        fontweight="semibold" if is_anchor else "regular",
+        color=INK,
+        ha="center",
+        va="bottom",
+        zorder=4,
+    )
+    ax.text(
+        row["angle_deg"],
+        label_y - 195,
+        f"{int(row['elevation_m'])} m",
+        fontsize=11,
+        color=INK_MUTED,
+        ha="center",
+        va="bottom",
+        zorder=4,
+    )
+
+# Highlight Matterhorn summit as the focal anchor
+matterhorn = peaks.loc[peaks["name"] == "Matterhorn"].iloc[0]
+ax.scatter(
+    [matterhorn["angle_deg"]],
+    [matterhorn["elevation_m"]],
+    s=110,
+    color=PAGE_BG,
+    edgecolor=BRAND,
+    linewidth=2.8,
+    zorder=6,
+)
+
+# Style
+ax.set_xlim(0, 200)
+ax.set_ylim(Y_FLOOR, LABEL_BASE_Y + LABEL_STAGGER + 600)
+ax.set_xlabel("Compass bearing", fontsize=20, color=INK)
+ax.set_ylabel("Elevation (m)", fontsize=20, color=INK)
+ax.set_title(
+    "Wallis 4000ers from Gornergrat · area-mountain-panorama · seaborn · anyplot.ai",
+    fontsize=24,
+    fontweight="medium",
+    color=INK,
+    pad=18,
+)
+
+ax.set_xticks([0, 50, 100, 150, 200])
+ax.set_xticklabels(["W", "SW", "S", "SE", "E"])
+ax.tick_params(axis="x", labelsize=16, colors=INK_SOFT, length=0)
+ax.tick_params(axis="y", labelsize=16, colors=INK_SOFT, length=0)
+
+ax.spines["top"].set_visible(False)
+ax.spines["right"].set_visible(False)
+ax.spines["left"].set_color(INK_SOFT)
+ax.spines["bottom"].set_color(INK_SOFT)
+ax.yaxis.grid(True, alpha=0.10, linewidth=0.8, color=INK)
+ax.set_axisbelow(True)
+
+plt.tight_layout()
+plt.savefig(f"plot-{THEME}.png", dpi=300, bbox_inches="tight", facecolor=PAGE_BG)