[SaladDay]

Removes text from CONTRIBUTING.md that is redundant or no longer true. Each fact that stays relevant keeps its owning document.

• Duplicates:
  • The second 'one owner' sentence.
  • The product and execution service separation bullets, owned by AGENTS.md and the Core service guide.
  • The Parsar example's ownership, bypass mode and accounts facts, owned by its README.
  • A pointer that only restates the simplicity principles.
  • The Harness catalog details, owned by Declare the Harness.
• Obsolete:
  • The external Parsar product's Core copy rule.
  • 'Product cursor replay', which has no producer.
  • Example projects, tasks, comments, Cron plans and Agent-scoped local MCP tokens; none exist in example/parsar.
  • Rename-era wording ('Current name', preserving identifiers in display copy).

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