docs: define adaptive problem-solving cycle

[iteathen]

Summary

• make assess → research → reassess the mandatory discovery loop for complex or large-scope work
• require repeated discovery when scope expands or confidence remains low
• add confidence-gated final planning vs rapid reconnaissance prototyping
• define unknown-source debugging via scoping plus temporary semantic checkpoints
• require broad failure collection across independent tests while failing fast on invalid prerequisites
• make the engineering record continuous across problem, reasoning, research, plans, prototypes, execution, qualification, and cleanup
• require local mandatory agent startup authorities to carry a compact form rather than assuming this account-level file is auto-discovered

Scope

Documentation/governance only. No runtime, schema, ABI, support, or compatibility claims change.

Validation

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