docs(readme): Add Installation section with ZIP download and WP-CLI command

Two clearly-labeled install methods at the top of the README so
users know how to get the plugin without scrolling:
  - WordPress Admin GUI: 3-step ZIP upload
  - WP-CLI one-liner with --activate flag

Both link directly to the v1.0.0 release ZIP on Gitea.

README.md

@@ -6,6 +6,28 @@
 
 ---
 
+## 📦 Installation
+
+**Latest release:** [v1.0.0](https://git.supported.systems/tigerstyle/tigerstyle-dash/releases/tag/v1.0.0) · [All releases](https://git.supported.systems/tigerstyle/tigerstyle-dash/releases)
+
+### Via WordPress Admin (GUI)
+
+1. Download [tigerstyle-dash-1.0.0.zip](https://git.supported.systems/tigerstyle/tigerstyle-dash/releases/download/v1.0.0/tigerstyle-dash-1.0.0.zip)
+2. In WordPress admin: **Plugins → Add New → Upload Plugin**, pick the ZIP
+3. Click **Activate Plugin** — settings appear under **TigerStyle Dash** in the sidebar
+
+### Via WP-CLI (terminal)
+
+```bash
+wp plugin install \
+  https://git.supported.systems/tigerstyle/tigerstyle-dash/releases/download/v1.0.0/tigerstyle-dash-1.0.0.zip \
+  --activate
+```
+
+**Requires:** WordPress 5.0+ · PHP 7.4+
+
+---
+
 ## 🏃‍♀️ Why TigerStyle Dash?
 
 **Because your website should be as fast as a cat's reflexes!**