Document T3 Code install methods (#1564)

Author: juliusmarminge

README.md

@@ -2,7 +2,7 @@
 
 T3 Code is a minimal web GUI for coding agents (currently Codex and Claude, more coming soon).
 
-## How to use
+## Installation
 
 > [!WARNING]
 > T3 Code currently supports Codex and Claude.
@@ -11,13 +11,43 @@ T3 Code is a minimal web GUI for coding agents (currently Codex and Claude, more
 > - Codex: install [Codex CLI](https://github.com/openai/codex) and run `codex login`
 > - Claude: install Claude Code and run `claude auth login`
 
+### Run without installing
+
 ```bash
 npx t3
 ```
 
-You can also just install the desktop app. It's cooler.
+### Desktop app
+
+Install the desktop app using whichever method fits your platform:
+
+#### Direct download
+
+[GitHub Releases](https://github.com/pingdotgg/t3code/releases)
+
+#### Windows (`winget`)
+
+Reference: [pingdotgg/t3code#1544](https://github.com/pingdotgg/t3code/issues/1544), [winget-pkgs manifest](https://github.com/microsoft/winget-pkgs/tree/master/manifests/t/T3Tools/T3Code/)
+
+```bash
+winget install T3Tools.T3Code
+```
+
+#### macOS (Homebrew)
+
+Reference: [t3-code cask](https://formulae.brew.sh/cask/t3-code#default)
+
+```bash
+brew install --cask t3-code
+```
 
-Install the [desktop app from the Releases page](https://github.com/pingdotgg/t3code/releases)
+#### Arch Linux (AUR)
+
+Reference: [t3code-bin](https://aur.archlinux.org/packages/t3code-bin)
+
+```bash
+yay -S t3code-bin
+```
 
 ## Some notes