feat(persona): build the shared expert-reviewer persona as a framework-neutral Agent Skill

The expert reviewer was only a hardcoded verdict_input dict inside the offline
simulation. Build it as the real, shared artifact target picture §8 calls for:
shared/skills/expert-reviewer/ — a SKILL.md persona prompt (energy-advisor / M&V
role + the realization-gap methodology the validator cannot compute) plus a
canonical references/example-verdict.json. shared/ stays pure data; the MAF side
reads it via portfolio_optimiser.persona.load_persona_example (call-time,
fail-fast) and the Claude-SDK sibling reads the same JSON with its own loader.

This de-stubs the simulation: its persona judgement (decision + rationale + traced
marker) is now sourced from the artifact at call time, not an inline literal — so
the shared persona is genuinely consumed and cannot rot silently. decision is
binary (approved/rejected, the FeedbackContract the run path accepts);
approved_with_adjustment is rejected there and lives only in the bundle seed
frontmatter + the promotion gate, so the realization correction is carried in the
rationale prose.

Load-bearing trio (tests/test_persona_skill_loadbearing.py), each proven RED on its
own detach: structure + framework-neutrality, the example is valid pipeline input
(incl. FeedbackContract, on a throwaway copy), and the simulation's marker follows
the artifact file. Suite 149->152.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MHR8iKxJRxDiDfNw8HZmWE

CLAUDE.md

@@ -100,6 +100,20 @@ Python ≥3.10. MAF (`agent-framework-core` 1.9.0). Pakkehåndtering: `uv`. To b
   lever på Claude-SDK-siden (minimal API-kjøring). Skriptet klient = MAF-side stillas, IKKE delt
   (`shared/` forblir framework-nøytralt). Kjøres `uv run python -m portfolio_optimiser.simulation`.
   Load-bearing: `tests/test_simulation_loadbearing.py` blir RØD når promoteringen detaches.
+- **Delt ekspert-persona som Agent Skill (§8, framework-nøytral):** ekspert-reviewer-personaen bor i
+  `shared/skills/expert-reviewer/` (`SKILL.md` + `references/example-verdict.json`) og er den ENE
+  delte artefakten begge stacker instansierer reviewer-en fra. `shared/` forblir REN DATA — MAF-siden
+  leser den via `portfolio_optimiser.persona.load_persona_example` (call-time, fail-fast), Claude-SDK-
+  søskenet med sin egen loader mot samme JSON. Dette AV-STUBBER simuleringen: persona-dommen (decision
+  + rationale + sporet markør) hentes nå fra artefaktet ved call-time, ikke en inline-literal — så
+  personaen er genuint konsumert og kan ikke råtne stille. **Decision er binær** (`approved`/`rejected`
+  — `FeedbackContract` run-stien tar; `approved_with_adjustment` avvises der, bor kun i bundle-seedens
+  frontmatter + promoterings-gaten); realiseringskorreksjonen lever i rationale-prosaen, ikke et tredje
+  enum. SKILL.md-prosaen nevner ALDRI en konkret framework (maf-guarden er import-formet). Load-bearing-
+  trio (`tests/test_persona_skill_loadbearing.py`): struktur+framework-nøytralitet (RØD på framework-
+  import), eksempelet er gyldig pipeline-input inkl. `FeedbackContract` (RØD på skjema-/kontrakt-drift,
+  på en throwaway-kopi — aldri den git-tracked fixturen), og sim-ens markør følger artefakt-fila (RØD i
+  det øyeblikk personaen re-inlines).
 - **STATE.md er local-only** (gitignored). Voyage session-state er efemert; STATE.md er kanonisk kontinuitet.
 - Prosess: Voyage-plugin (`/trekbrief → /trekplan → /trekexecute → /trekreview`) per større fase.