add camera rig, click-to-move locomotion, and click interaction

Camera: Cinemachine-based rig with an anchor, a state director, point-of-
interest framing, pan input, and dialogue framing volumes.

Player: click-to-move over the NavMesh, a pointer input layer, and a motion
arbiter that reconciles direct stick input with navigation-driven movement.
The pure math is isolated in NightclubArcadia.Locomotion.Math with an EditMode
suite, so the arbitration rules are testable without a scene.

Interaction: IClickInteractable plus a bridge that routes pointer clicks to it.

Supporting project settings: adds the Cinemachine package, the Interactable and
Ground tags the raycasts depend on, and NavMesh agent dimensions matched to the
player capsule (radius 0.3, height 1.8, climb 0.25).

Co-Authored-By: Claude Opus 5 <[email protected]>

NightclubArcadia/Packages/packages-lock.json

@@ -21,7 +21,7 @@
     },
     "com.unity.cinemachine": {
       "version": "3.1.7",
-      "depth": 1,
+      "depth": 0,
       "source": "registry",
       "dependencies": {
         "com.unity.splines": "2.0.0",
@@ -84,7 +84,7 @@
     },
     "com.unity.mathematics": {
       "version": "1.4.0",
-      "depth": 3,
+      "depth": 2,
       "source": "builtin",
       "dependencies": {}
     },
@@ -168,7 +168,7 @@
     },
     "com.unity.splines": {
       "version": "2.9.0",
-      "depth": 2,
+      "depth": 1,
       "source": "registry",
       "dependencies": {
         "com.unity.mathematics": "1.2.1",