chore: separate install docs (#3859)

docs/install/binary.md

@@ -0,0 +1,34 @@
+Coder publishes self-contained .zip and .tar.gz archives in [GitHub releases](https://github.com/coder/coder/releases). The archives bundle `coder` binary.
+
+1. Download the [release archive](https://github.com/coder/coder/releases) appropriate for your operating system
+
+1. Unzip the folder you just downloaded, and move the `coder` executable to a location that's on your `PATH`
+
+   ```sh
+   # ex. macOS and Linux
+   mv coder /usr/local/bin
+   ```
+
+   > Windows users: see [this guide](https://answers.microsoft.com/en-us/windows/forum/all/adding-path-variable/97300613-20cb-4d85-8d0e-cc9d3549ba23) for adding folders to `PATH`.
+
+1. Start a Coder server
+
+   ```sh
+   # Automatically sets up an external access URL on *.try.coder.app
+   coder server --tunnel
+
+   # Requires a PostgreSQL instance and external access URL
+   coder server --postgres-url <url> --access-url <url>
+   ```
+
+   > Set `CODER_ACCESS_URL` to the external URL that users and workspaces will use to
+   > connect to Coder. This is not required if you are using the tunnel. Learn more
+   > about Coder's [configuration options](../admin/configure.md).
+
+1. Visit the Coder URL in the logs to set up your first account, or use the CLI.
+
+## Next steps
+
+- [Quickstart](../quickstart.md)
+- [Configuring Coder](../admin/configure.md)
+- [Templates](../templates.md)