feat(agents): pin dispatched judgment agents to opus — Fable = inline reflection only (BDR-076)

Reverses the BDR-066 rejected alternative (opus pins on audit agents):
session default is now Fable, so inherit burned Fable quota on every
dispatched audit/challenge. analyzer, plan-challenger, seo/geo/
validator-analyzer pinned model: opus; onboard's 6 general-purpose
audit dispatches carry model="opus"; tour Phase B repointed.
interviewer + client-handover-writer stay unpinned (inline-load only,
a pin there is inert). settings.json default: claude-fable-5[1m].
Census flipped: model-routing §3 + new §11 (61 pass), loops-light 35,
full make test green.

skills/tour/SKILL.md

@@ -111,9 +111,9 @@ honestly in the summary. Never loop past 3.
 
 ### Phase B — CLEAN
 
-1. Dispatch a read-only cleanup audit (analyzer or general-purpose —
-   inherits the big session model; NOT the sonnet code-cleaner, which is
-   now a fix executor): dead code, unused imports/exports,
+1. Dispatch a read-only cleanup audit (analyzer — opus-pinned, BDR-076 —
+   or general-purpose with `model="opus"`; NOT the sonnet code-cleaner,
+   which is now a fix executor): dead code, unused imports/exports,
    commented-out blocks, stale flags, norm violations. Findings as
    `id | file:line | finding | proposed fix`.
 2. Apply **behavior-preserving** fixes only. A finding that would change