📖 [Docs]: Add a Specify-the-minimum (Lean) principle and Non-goals to the spec standard

[Marius Storhaug (MariusStorhaug)]

The spec standard now names an explicit minimalism principle and gives every spec a place to state its non-goals — two structural lessons borrowed from how Google's Open Knowledge Format is written. This mirrors the same change made to the AI-Platform copy of the standard, keeping the two in sync.

New: A "Specify the minimum" principle

The standard gains a short Specify the minimum section: a spec fixes the smallest set of requirements that make the capability correct and verifiable, and leaves every other choice to the design and the people building it, because over-specification is waste. It grounds the idea in the existing Lean Software Development principle and points at the altitude test as how it is applied.

New: A Non-goals element

Both the standard's "a spec contains" list and the inline specification template gain Non-goals — the outcomes a capability deliberately does not pursue, named so its intent is not misread. It sits beside Scope but is distinct: out of scope bounds this change; non-goals bound the intent.

A third idea considered from OKF — a dedicated worked-example section — was deliberately skipped: the Given/When/Then acceptance criteria already carry that weight for a feature spec, and OKF's heavier interoperability machinery (conformance, producer/consumer obligations, artifact versioning) belongs only to specs that define a contract.

Technical Details

• src/docs/Ways-of-Working/Spec-Driven-Development.md — new ## Specify the minimum section; a Non-goals bullet in the "A spec contains" list; a ## Non-goals heading in the inline specification template.
• Index check, link validation, and markdownlint all pass locally.
• Companion change: the AI-Platform mirror of this standard receives the same update.