macos-native: clean branch for cloning and building the Tauri desktop app

Orphan branch with no history — includes the Tauri shell (src-tauri/) and
vendored Three.js (vendor/) that were never pushed before, so a fresh clone
can actually build the native app. Drops the large .pcd sample captures and
editor cruft (.obsidian, .DS_Store); they aren't needed to build or run the
app (point clouds load via drag-and-drop, not bundling).

src-tauri/tauri.conf.json

@@ -0,0 +1,37 @@
+{
+  "$schema": "https://schema.tauri.app/config/2",
+  "productName": "PCD Viewer",
+  "version": "0.1.0",
+  "identifier": "com.khj.pcdviewer",
+  "build": {
+    "frontendDist": "./web",
+    "beforeDevCommand": "sh ./src-tauri/stage-web.sh",
+    "beforeBuildCommand": "sh ./src-tauri/stage-web.sh"
+  },
+  "app": {
+    "windows": [
+      {
+        "url": "pcd_viewer.html",
+        "title": "PCD Viewer",
+        "width": 1440,
+        "height": 900,
+        "minWidth": 960,
+        "minHeight": 640,
+        "backgroundColor": "#0a0b0c",
+        "dragDropEnabled": false
+      }
+    ],
+    "security": {
+      "csp": "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data: blob:; connect-src 'self' blob: data: ws: wss:; worker-src 'self' blob:",
+      "dangerousDisableAssetCspModification": ["script-src", "style-src"]
+    }
+  },
+  "bundle": {
+    "active": true,
+    "targets": ["app", "dmg"],
+    "icon": ["icons/icon.icns"],
+    "macOS": {
+      "minimumSystemVersion": "10.15"
+    }
+  }
+}