docs: add Homebrew installation instructions

- README.md: Add Homebrew as primary install method
- getting-started.md: Add Homebrew, manual download, and from-source sections

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: BjoernSchotte

README.md

@@ -38,6 +38,14 @@ A blazingly fast CLI for Atlassian products. Sync Confluence pages as markdown,
 
 ## Installation
 
+### Homebrew (macOS & Linux)
+
+```bash
+brew install bjoernschotte/tap/atlcli
+```
+
+### From Source
+
 ```bash
 git clone https://github.com/BjoernSchotte/atlcli.git
 cd atlcli

docs/getting-started.md

@@ -4,12 +4,47 @@ This guide walks you through installing atlcli, authenticating with Atlassian, a
 
 ## Installation
 
-### Prerequisites
+### Homebrew (Recommended)
 
-- [Bun](https://bun.sh) v1.0 or later
-- An Atlassian Cloud account
+The easiest way to install atlcli on macOS or Linux:
+
+```bash
+brew install bjoernschotte/tap/atlcli
+```
+
+This installs the latest release and adds `atlcli` to your PATH automatically.
+
+To upgrade to a newer version:
+
+```bash
+brew upgrade atlcli
+```
+
+### Manual Download
 
-### Install from Source
+Download the latest release for your platform from the [releases page](https://github.com/BjoernSchotte/atlcli/releases):
+
+| Platform | File |
+|----------|------|
+| macOS (Apple Silicon) | `atlcli-darwin-arm64.tar.gz` |
+| macOS (Intel) | `atlcli-darwin-x64.tar.gz` |
+| Linux (ARM64) | `atlcli-linux-arm64.tar.gz` |
+| Linux (x64) | `atlcli-linux-x64.tar.gz` |
+
+Extract and add to your PATH:
+
+```bash
+tar -xzf atlcli-*.tar.gz
+sudo mv atlcli /usr/local/bin/
+```
+
+### From Source
+
+For development or if you want the latest unreleased changes:
+
+**Prerequisites:**
+
+- [Bun](https://bun.sh) v1.0 or later
 
 ```bash
 git clone https://github.com/BjoernSchotte/atlcli.git