Add Cinemachine third-person orbit camera and fix paint raycast

- Install Cinemachine 3.1.7 and set up an orbital third-person camera rig
  (CinemachineBrain, OrbitalFollow, RotationComposer, Deoccluder).
- Add ThirdPersonOrbitInput: mouse-driven orbit and wheel zoom with a Tab
  toggle that unlocks the cursor and pauses rotation.
- Fix MeshPainter so the paint ray skips the player's CharacterController
  capsule (and any other collider) and always targets the mesh collider,
  so painting works from every camera angle.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Packages/manifest.json

@@ -1,6 +1,7 @@
 {
   "dependencies": {
     "com.coplaydev.unity-mcp": "https://github.com/CoplayDev/unity-mcp.git?path=/MCPForUnity#main",
+    "com.unity.cinemachine": "3.1.7",
     "com.unity.ide.visualstudio": "2.0.27",
     "com.unity.inputsystem": "1.19.0",
     "com.unity.multiplayer.center": "1.0.1",

Packages/packages-lock.json

@@ -27,6 +27,16 @@
       },
       "url": "https://packages.unity.com"
     },
+    "com.unity.cinemachine": {
+      "version": "3.1.7",
+      "depth": 0,
+      "source": "registry",
+      "dependencies": {
+        "com.unity.splines": "2.0.0",
+        "com.unity.modules.imgui": "1.0.0"
+      },
+      "url": "https://packages.unity.com"
+    },
     "com.unity.collections": {
       "version": "2.6.2",
       "depth": 2,
@@ -132,6 +142,13 @@
       "dependencies": {},
       "url": "https://packages.unity.com"
     },
+    "com.unity.settings-manager": {
+      "version": "2.1.1",
+      "depth": 2,
+      "source": "registry",
+      "dependencies": {},
+      "url": "https://packages.unity.com"
+    },
     "com.unity.shadergraph": {
       "version": "17.3.0",
       "depth": 1,
@@ -141,6 +158,17 @@
         "com.unity.searcher": "4.9.3"
       }
     },
+    "com.unity.splines": {
+      "version": "2.8.3",
+      "depth": 1,
+      "source": "registry",
+      "dependencies": {
+        "com.unity.mathematics": "1.2.1",
+        "com.unity.modules.imgui": "1.0.0",
+        "com.unity.settings-manager": "1.0.3"
+      },
+      "url": "https://packages.unity.com"
+    },
     "com.unity.test-framework": {
       "version": "1.6.0",
       "depth": 1,