feat(model-router): wave 2-B — orchestrators declare phases, shifters and pins removed, frontmatter = off-state floor

The 15 Skill(effort-*) citers now call mcp__model-router__route per phase
(orchestrate at a dispatch span, reflect/plan for the skill's own level,
apply at the bookkeeping tail, escalate at the verify-secure caps); built-in
judgment dispatches carry an explicit effort= param. lib/effort-shift.md is
the route doctrine, lib/model-gate.md the mod rule (route answer = witness,
/route on as remedy). Deleted: skills/effort-*, lib/effort-pins.txt/.sh,
lib/model-check.sh, their tests, the installers' re-apply blocks. The mod
drops its Skill(effort-*) bridge. The tracked model:/effort: frontmatter
stays as the off-state floor, census-locked equal to the rows
(lib/tests/effort-routing.test.sh rewritten, 140 checks; analyzer → xhigh).

Contract .claude/tasks/contracts/2026-10-10-model-router-w2b-1045.md, plan
r4 § W2-B: GATE 0 MET, verifier ECARTS(7) then CONFORME 10/10, security
PASS, full make test green (design-tool-gate env red only).

skills/audit-delta/SKILL.md

@@ -29,7 +29,7 @@ Run `$HOME/.claude/lib/model-gate.md`. Reflection here (planning, audit
 judgment, loop decisions) requires Fable/Opus. Verdict `small` → STOP: the
 gate prints the remedy; end the turn — no later step, no dispatch. Nominal
 (big) path is silent.
-EFFORT SHIFTS: follow `$HOME/.claude/lib/effort-shift.md` (BDR-107): medium when a dispatch span starts, own level before challenge synthesis, low at the bookkeeping tail, max at escalation; every shift goes in the same message as the step's first tool call, a lone Skill call is a no-op.
+ROUTING: follow $HOME/.claude/lib/effort-shift.md (phases via mcp__model-router__route).
 
 Audit only what changed since the last run, on the axes the user picks.
 Per axis: **audit → approval gate → fix → re-verify → marker update**,
@@ -170,7 +170,7 @@ Then show the user the same compact table inline.
 
 ### 3b-bis. CHALLENGE THE PROPOSALS (before the gate)
 
-`Skill(effort-xhigh)` first (effort-shift: own level before the challenge; send it in the same message as the challenger dispatch).
+`mcp__model-router__route(phase="plan")` first (route: own level before the challenge; send it with the challenger dispatch).
 This axis' findings + proposed fixes are a proposal set worth attacking before
 the human gate. Persist THIS axis' finding list (not the whole append-only
 report) to `.claude/tasks/plans/<date>-<axis>-<HHMM>.md`, then run
@@ -256,7 +256,7 @@ Then offer to capitalize (per CLAUDE.md): recurring finding patterns →
   below on the same delta (the SAST is a deterministic floor, the reasoned
   pass covers what grep/rules miss):
   ```
-  Skill(effort-medium)   # effort-shift: dispatch span starts; send with the Agent call below in ONE message
+  mcp__model-router__route(phase="orchestrate")   # route: dispatch span starts; send with the Agent call below in ONE message
   Agent(subagent_type="security-auditor", description="audit-delta security — semgrep SAST",
     prompt="MODE: audit\nSCOPE: <delta file list>\nREPORT: .claude/audits/.audit-delta-semgrep.md\nFollow agents/security-auditor.md exactly. Pinned rulesets, no login. Write ONLY to REPORT. End with REPORT_WRITTEN: <path>.")
   ```