v3 : socle Rust (moteur pur, accès trustinWallet, serveur) ; maquette Nuxt rangée dans maquette/

- crates/ld-engine : formule inertielle (parité avec la maquette, garde C),
  coquille / changement de fond, assistant d'édition à règles, composition
  d'un document sous vote permanent (adoptions, aperçus, rivales).
- crates/trustin-access : qui voit, qui ouvre, qui gère les accès.
- crates/ld-server : API axum + SQLite, connexion Ğ1 (client OAuth2 de
  connect.monnaie-libre.fr), invitations, entrée en vigueur automatique,
  signalements de contradiction, traductions éditoriales, publication git,
  taille de la toile lue sur la chaîne.
- seeds/acte-engagement-certification.json : 33 articles, fr + en + es ;
  en vigueur : préambule, E1, E2 (seed a minima).
- maquette/ : frontend, backend et docker v2 déplacés tels quels.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

maquette/frontend/app/engine/nuanced.ts

@@ -0,0 +1,109 @@
+/**
+ * Six-level nuanced vote evaluation.
+ *
+ * Exact TypeScript port of backend/app/engine/nuanced_vote.py
+ * (Python is the reference implementation).
+ *
+ * Levels:
+ *   0 - CONTRE
+ *   1 - PAS DU TOUT
+ *   2 - PAS D'ACCORD
+ *   3 - NEUTRE
+ *   4 - D'ACCORD
+ *   5 - TOUT A FAIT
+ *
+ * Adoption rule:
+ *   The sum of votes at levels 3 + 4 + 5 must be >= thresholdPct% of total votes.
+ *   A minimum number of participants is also required.
+ */
+
+export const LEVEL_LABELS: Record<number, string> = {
+  0: 'CONTRE',
+  1: 'PAS DU TOUT',
+  2: "PAS D'ACCORD",
+  3: 'NEUTRE',
+  4: "D'ACCORD",
+  5: 'TOUT A FAIT',
+}
+
+export const NUM_LEVELS = 6
+
+/** Result shape mirrors the Python dict returned by evaluate_nuanced(). */
+export interface NuancedResult {
+  total: number
+  per_level_counts: Record<number, number>
+  positive_count: number
+  positive_pct: number
+  threshold_met: boolean
+  min_participants_met: boolean
+  adopted: boolean
+}
+
+/**
+ * Round to 2 decimals with ties-to-even, mirroring Python's round(x, 2).
+ */
+function round2(value: number): number {
+  const scaled = value * 100
+  const floor = Math.floor(scaled)
+  const diff = scaled - floor
+  let rounded: number
+  if (diff > 0.5) {
+    rounded = floor + 1
+  } else if (diff < 0.5) {
+    rounded = floor
+  } else {
+    rounded = floor % 2 === 0 ? floor : floor + 1
+  }
+  return rounded / 100
+}
+
+/**
+ * Evaluate a nuanced vote from a list of individual vote levels.
+ *
+ * @param votes - List of vote levels (each 0-5), one entry per voter
+ * @param thresholdPct - Minimum percentage of positive votes (levels 3-5) for adoption
+ * @param minParticipants - Minimum number of participants required for validity
+ * @returns Aggregated result (counts, percentage, adoption flags)
+ * @throws Error if any vote value is outside the 0-5 integer range
+ */
+export function nuancedResult(
+  votes: number[],
+  thresholdPct: number = 80,
+  minParticipants: number = 59,
+): NuancedResult {
+  // Validate vote levels (integer check added: JS has no KeyError safety net)
+  for (const v of votes) {
+    if (!Number.isInteger(v) || v < 0 || v > 5) {
+      throw new Error(`Niveau de vote invalide : ${v}. Les niveaux valides sont 0-5.`)
+    }
+  }
+
+  const total = votes.length
+
+  const perLevelCounts: Record<number, number> = {}
+  for (let level = 0; level < NUM_LEVELS; level++) {
+    perLevelCounts[level] = 0
+  }
+  for (const v of votes) {
+    perLevelCounts[v] = (perLevelCounts[v] ?? 0) + 1
+  }
+
+  // Positive = levels 3 (NEUTRE), 4 (D'ACCORD), 5 (TOUT A FAIT)
+  const positiveCount = (perLevelCounts[3] ?? 0) + (perLevelCounts[4] ?? 0) + (perLevelCounts[5] ?? 0)
+
+  const positivePct = total > 0 ? (positiveCount / total) * 100.0 : 0.0
+
+  const thresholdMet = positivePct >= thresholdPct
+  const minParticipantsMet = total >= minParticipants
+  const adopted = thresholdMet && minParticipantsMet
+
+  return {
+    total,
+    per_level_counts: perLevelCounts,
+    positive_count: positiveCount,
+    positive_pct: round2(positivePct),
+    threshold_met: thresholdMet,
+    min_participants_met: minParticipantsMet,
+    adopted,
+  }
+}