docs: add Scarf usage-analytics pixel to docs + README

Co-Authored-By: Alex Schapiro <bearsyankees@gmail.com>

docs/tools/browser.mdx

@@ -3,6 +3,10 @@ title: "Browser"
 description: "Playwright-powered Chrome for web application testing"
 ---
 
+import { ScarfPixel } from "/snippets/scarf-pixel.mdx";
+
+<ScarfPixel />
+
 Strix uses a headless Chrome browser via Playwright to interact with web applications exactly like a real user would.
 
 ## How It Works

docs/tools/overview.mdx

@@ -3,6 +3,10 @@ title: "Agent Tools"
 description: "How Strix agents interact with targets"
 ---
 
+import { ScarfPixel } from "/snippets/scarf-pixel.mdx";
+
+<ScarfPixel />
+
 Strix agents use specialized tools to test your applications like a real penetration tester would.
 
 ## Core Tools

docs/tools/proxy.mdx

@@ -3,6 +3,10 @@ title: "HTTP Proxy"
 description: "Caido-powered proxy for request interception and replay"
 ---
 
+import { ScarfPixel } from "/snippets/scarf-pixel.mdx";
+
+<ScarfPixel />
+
 Strix includes [Caido](https://caido.io), a modern HTTP proxy built for security testing. All browser traffic flows through Caido, giving the agent full control over requests and responses.
 
 ## Capabilities

docs/tools/sandbox.mdx

@@ -3,6 +3,10 @@ title: "Sandbox Tools"
 description: "Pre-installed security tools in the Strix container"
 ---
 
+import { ScarfPixel } from "/snippets/scarf-pixel.mdx";
+
+<ScarfPixel />
+
 Strix runs inside a Kali Linux-based Docker container with a comprehensive set of security tools pre-installed. The agent can use any of these tools through the [terminal](/tools/terminal).
 
 ## Reconnaissance

docs/tools/terminal.mdx

@@ -3,6 +3,10 @@ title: "Terminal"
 description: "Bash shell for running commands and security tools"
 ---
 
+import { ScarfPixel } from "/snippets/scarf-pixel.mdx";
+
+<ScarfPixel />
+
 Strix has access to a persistent bash terminal running inside the Docker sandbox. This gives the agent access to all [pre-installed security tools](/tools/sandbox).
 
 ## Capabilities