Added basic 3D FPP example of movement and look around. (#131)

* Added basic 3D FPP example of movement and look around.

* Fixed name of the character controller script.

Author: paweljarosz

movement/3d_fps/all.texture_profiles

@@ -0,0 +1,18 @@
+path_settings {
+  path: "**"
+  profile: "Default"
+}
+profiles {
+  name: "Default"
+  platforms {
+    os: OS_ID_GENERIC
+    formats {
+      format: TEXTURE_FORMAT_RGBA
+      compression_level: BEST
+      compression_type: COMPRESSION_TYPE_DEFAULT
+    }
+    mipmaps: false
+    max_texture_size: 0
+    premultiply_alpha: true
+  }
+}

movement/3d_fps/collection.png

@@ -0,0 +1,53 @@
+---
+tags: movement
+title: First-person 3D camera and movement
+brief: Control a first-person camera using WASD and mouse to look with cursor lock.
+author: Defold Foundation
+scripts: character_controller.script
+thumbnail: collection.png
+---
+
+This example shows how to build a simple first-person controller for a 3D scene. You can look around with the mouse and move on the XZ plane using the keyboard (WSAD).
+
+## What you'll learn?
+- How to implement a FPP camera with mouse to look around.
+- How to lock/unlock the mouse cursor for immersive camera control.
+- How to move on a simple XZ plane logic with keyboard input.
+
+## Controls
+| Input                  | Action                                               |
+|------------------------|------------------------------------------------------|
+| Left mouse click       | Lock the cursor and enable mouse look                |
+| Mouse movement         | Rotate camera                                        |
+| `Esc`                  | Unlock the cursor                                    |
+| `W`/`S`/`A`/`D`        | Move forward/backward/left/right on the ground plane |
+
+## How it works?
+When the cursor is locked, the script reads mouse movement deltas and rotates the camera accordingly. Movement is normalized to keep a consistent speed in all directions and is clamped within a square area so you cannot wander off the demo scene.
+
+Example collection consists of 3 main parts:
+
+- `character` - The player character game object includes:
+  - A *script* `character_controller.script` component that implements mouse look, cursor lock/unlock, and WASD movement.
+  - A *camera* component configured with perspective projection.
+
+- `scene` - the models used to create a basic 3D environment:
+  - Ground plane scaled to form a walkable area with prototype texture
+  - Walls built from simple cube models with prototype textures
+  - Some decorative trees
+
+- `gui` - An on-screen GUI with short instructions.
+
+![](collection.png)
+
+### Assets
+Tree models with textures by Kay Louseberg: https://kaylousberg.itch.io/kaykit-forest
+Prototype textures for Defold by Visionaire: https://github.com/Thevisionaire1/3Deforms
+
+## Script
+
+Tuning parameters are defined at the top of `character_controller.script`:
+- `look_sensitivity` (degrees per pixel) controls how fast the camera rotates
+- `move_speed` (world units per second) controls walking speed
+- `move_limit` (half-size in world units) clamps movement within bounds
+