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Add introductory content for Self-Healing CI project

Author: fraware

README.md

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 # Self-Healing CI
 
 **React to broken CI with context, diagnosis, and an automated fix path** — a GitHub App plus Temporal worker that collects failure data, asks Claude for a root cause and patch, applies changes via GitHub or Morph, runs tests and optional proof checks, then updates status or merges when your policy allows.
 
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 ## At a glance