docs(doctrine): model tiers in model-roles.md; prose asks replace tool prompts

[Exploitacious]

Two documentation sweeps, no behavior change.

• Operating-doctrine Principle 12 keeps its orchestration content and points at CONTEXT/model-roles.md for the tier table instead of restating it. Cross-references that named the old bullet get a superseding history entry.
• Instructions that told a session to use an interactive option-list tool now say to put the shaping questions to the operator in prose and wait. One retirement note stays in working-preferences.md; the fleet don't-render rules and the harness-audit lane prompt use tool-agnostic wording.

Gate: verify-ops 17 ok / 6 warn (environmental) / 0 fail, unchanged from baseline. Identifier grep on every touched file: zero hits.