add more contributing documentation

CONTRIBUTING.md

@@ -8,9 +8,15 @@ For small bug-fixes, documentation updates, or other trivial changes, feel free
 
 If the changes are larger (API design, architecture, etc), [opening an issue](https://github.com/player-ui/player/issues/new/choose) can be helpful to reduce implementation churn as we hash out the design.
 
-## Building and Testing Locally
+## Requirements
+* [npm >= 8.19.2](https://docs.npmjs.com/downloading-and-installing-node-js-and-npm)
+* [yarn >= 1.22.19](https://yarnpkg.com/)
+* [Swift >= 5.2](https://www.swift.org/download/)
+* [Android NDK = 19.2.5345600](https://github.com/android/ndk/wiki/Unsupported-Downloads#r19c). You'll need to add `ANDROID_NDK_HOME` to your environment manually.
 
-For speed and consistency, this repo leverages `bazel` as it's main build tool.
+## Building and Testing Locally
+### Player
+For speed and consistency, this repo leverages `bazel` as it's main build tool. Check out the [bazel](https://bazel.build/) docs for more info.
 
 After forking the repo, run builds using:
 
@@ -23,7 +29,16 @@ Tests can also be ran using:
 ```bash
 bazel test //...
 ```
-Check out the [bazel](https://bazel.build/) docs for more info.
+
+### Docs Sites
+These require the [Android NDK](https://developer.android.com/ndk).
+The docs site can be ran using:
+
+```bash
+bazel build //docs/site:start
+bazel run //docs/site:start
+```
+which will run an instance on `http://localhost:3000`.
 
 
 ## Submitting a Pull Request