docs(readme): point Get Started at the 14-day Cloud trial

[mortondev]

Retarget the README Get Started Cloud CTA so GitHub traffic starts a Cloud trial instead of a vague “start free” line. Draft only — do not merge.

What changed

README.md Get Started block only:

• Cloud line is now the 14-day trial copy, linking to https://app.quackback.io/signup
• Self-host remains secondary (Docker / Railway), AGPL-3.0
• No other README copy, star badges, or unrelated files

Requested files not in this repo

These live on the separate quackback.io marketing site, not QuackbackIO/quackback. Skipped as instructed:

• Compare Switch CTAs (/compare/quackback-vs-canny, /compare/quackback-vs-featurebase, and sibling compare pages using the shared compare-cta component)
• blog/canny-vs-featurebase (Fibi $0.29 → $0.49)
• blog/welcome (free Cloud plan → 14-day trial)
• Compare tables still showing Canny Core $19

No surrounding marketing copy was invented or rewritten.

  

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