chore: update npm references to @envcheck/cli

Author: skew202

content/introduction/_index.md

@@ -24,7 +24,7 @@ Get up and running in seconds:
 
 ```bash
 # Install via npm
-npx envcheck@latest init
+npx @envcheck/cli@latest init
 
 # Or via cargo
 cargo install envcheck

content/introduction/installation.md

@@ -31,9 +31,9 @@ brew install envcheck
 ## npm
 
 ```bash
-npm install -g envcheck
+npm install -g @envcheck/cli
 # Or use without installing:
-npx envcheck lint .env
+npx @envcheck/cli lint .env
 ```
 
 ## Docker

content/whats-new/v1-0-0.md

@@ -47,7 +47,7 @@ envcheck is a fast, modern Rust CLI for linting `.env` files and DevSecOps integ
 cargo install envcheck
 
 # npm
-npm install -g envcheck
+npm install -g @envcheck/cli
 
 # Homebrew
 brew tap envcheck/tap && brew install envcheck

content/whats-new/v1-1-0.md

@@ -29,5 +29,5 @@ weight = 1
 cargo install envcheck@1.1.0
 
 # or npm
-npm install -g envcheck@1.1.0
+npm install -g @envcheck/cli@1.1.0
 ```