Реструктуризация проекта и генератор синтетических датасетов эхолота.

Перенесены backend/frontend/desktop/engine, добавлены вкладки конструктора сцен и генератора датасета с параметрами лучей и длины сетки рельефа, обновлены API и Docker-сборка.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/demo_generator.py

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+"""Demo point cloud generation (mirrors generateDemoPoints in mainwindow.cpp)."""
+
+from __future__ import annotations
+
+import math
+import random
+from typing import Any
+
+
+def generate_demo_points(surface_type: str, count: int = 350) -> list[list[float]]:
+    points: list[list[float]] = []
+    rng = random.Random()
+
+    for _ in range(count):
+        if surface_type == "Дно реки + труба":
+            if rng.random() < 0.35:
+                angle = rng.random() * 2.0 * math.pi
+                y = rng.random() * 2.6 - 1.3
+                pipe_radius = 0.22
+                jitter = rng.random() * 0.02 - 0.01
+                radial = pipe_radius + jitter
+                x = 0.0 + radial * math.cos(angle)
+                z = -0.62 + radial * math.sin(angle)
+            else:
+                x = rng.random() * 4.0 - 2.0
+                y = rng.random() * 3.0 - 1.5
+                waviness = 0.11 * math.cos(2.2 * y)
+                channel = 0.08 * x * x
+                noise = rng.random() * 0.04 - 0.02
+                z = -0.45 + channel + waviness + noise
+        elif surface_type == "Тор":
+            u = rng.random() * 2.0 * math.pi
+            v = rng.random() * 2.0 * math.pi
+            major_r = 1.0
+            minor_r = 0.35
+            jitter = rng.random() * 0.02 - 0.01
+            radial = minor_r + jitter
+            x = (major_r + radial * math.cos(v)) * math.cos(u)
+            y = (major_r + radial * math.cos(v)) * math.sin(u)
+            z = radial * math.sin(v)
+        elif surface_type == "Волна":
+            x = rng.random() * 2.4 - 1.2
+            y = rng.random() * 2.4 - 1.2
+            noise = rng.random() * 0.03 - 0.015
+            z = 0.35 * math.sin(2.5 * x) * math.cos(2.5 * y) + noise
+        else:
+            u = rng.random() * 2.0 - 1.0
+            theta = rng.random() * 2.0 * math.pi
+            r = 1.0 + rng.random() * 0.08 - 0.04
+            s = math.sqrt(max(0.0, 1.0 - u * u))
+            x = r * s * math.cos(theta)
+            y = r * s * math.sin(theta)
+            z = r * u
+        points.append([x, y, z])
+    return points
+
+
+DEMO_SURFACE_TYPES = ["Сфера", "Тор", "Волна", "Дно реки + труба"]
+
+
+def demo_payload(surface_type: str, count: int = 350) -> dict[str, Any]:
+    if surface_type not in DEMO_SURFACE_TYPES:
+        surface_type = "Сфера"
+    points = generate_demo_points(surface_type, count)
+    return {
+        "surfaceType": surface_type,
+        "pointCount": len(points),
+        "points": points,
+        "sourceLabel": f"demo: {surface_type}",
+    }