v9.5.2

Treat ghul-runtime as the one source library (#168)

Technical:

• Remove the core library as a library of its own: ghul-runtime, which
  carries the core sources, is the only implicit library
• A ghul-core declaration is ignored, with a warning on the project's
  own manifest saying to remove it
• The wasm loader comes only from the runtime library's core tree; the
  fallbacks for a separate core checkout are gone
• The READMEs, AGENTS.md and tests describe and use one library

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Co-authored-by: ghul-coder[bot] <286450068+ghul-coder[bot]@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 noreply@anthropic.com