Add Plausible Analytics to Your App

I want to add Plausible Analytics to my website so I can track visitors without cookies or GDPR consent banners.

Project details:
- Website URL: [your domain, e.g. myapp.com]
- Framework: [e.g. Next.js, Astro, plain HTML, WordPress]
- Plausible plan: [Cloud (paid) or Self-hosted]
- Key pages I want to track: [e.g. homepage, pricing, signup, dashboard]

Please help me with:

1. Script installation:
   - Give me the exact script tag to add to my site's [head] section
   - Show me where to place it in my framework: [framework name]
   - If using Next.js, show me the next/script approach with the correct strategy
   - If using Astro, show me where to add it in my Base layout
   - Confirm the script is only 1KB and won't affect page speed

2. Custom event tracking:
   Set up these specific events so I can measure what matters:
   - Signup button clicked: fire when someone clicks [signup CTA location]
   - Pricing page viewed: fire on /pricing page load
   - Free trial started: fire when [trigger, e.g. "form submitted on /signup"]
   - Feature used: fire when [specific action, e.g. "user creates first project"]

   For each event, give me the exact JavaScript call:
   plausible('Event Name', [props: ...])

3. Goal setup in Plausible dashboard:
   - Create a goal for each custom event above
   - Set up a pageview goal for my conversion page: [e.g. /welcome, /thank-you]
   - Explain how to see conversion rates from traffic source to goal completion

4. UTM campaign tracking:
   - Show me how to structure UTM links for my campaigns
   - Give me 3 example URLs for: [a newsletter link, a Twitter post, a Product Hunt launch]
   - Explain where these show up in the Plausible dashboard

5. Optional extras:
   - Set up a custom 404 page tracker
   - Exclude my own visits during development
   - Share a public dashboard link with my team (read-only)

Write all code snippets ready to copy-paste. Keep explanations short — I just need it working.