Sprint 4 : decisions et mandats -- workflow complet + vote integration

Backend: 7 nouveaux endpoints (advance, assign, revoke, create-vote-session),
services enrichis avec creation de sessions de vote, assignation de mandataire
et revocation. 35 nouveaux tests (104 total). Frontend: store mandates, page
cadrage decisions, detail mandats, composants DecisionWorkflow, DecisionCadrage,
DecisionCard, MandateTimeline, MandateCard. Documentation mise a jour.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/app/components/mandates/MandateTimeline.vue

@@ -0,0 +1,138 @@
+<script setup lang="ts">
+/**
+ * Visual timeline for mandate lifecycle steps.
+ *
+ * Displays each step with its type, status, and visual indicators.
+ * Similar pattern to DecisionWorkflow but with mandate-specific step types.
+ */
+import type { MandateStep } from '~/stores/mandates'
+
+const props = defineProps<{
+  steps: MandateStep[]
+  currentStatus: string
+}>()
+
+const sortedSteps = computed(() => {
+  return [...props.steps].sort((a, b) => a.step_order - b.step_order)
+})
+
+const stepTypeLabel = (stepType: string) => {
+  switch (stepType) {
+    case 'candidacy': return 'Candidature'
+    case 'voting': return 'Vote'
+    case 'active': return 'Actif'
+    case 'reporting': return 'Rapport'
+    case 'completed': return 'Termine'
+    default: return stepType
+  }
+}
+
+const stepTypeIcon = (stepType: string) => {
+  switch (stepType) {
+    case 'candidacy': return 'i-lucide-user-plus'
+    case 'voting': return 'i-lucide-vote'
+    case 'active': return 'i-lucide-shield-check'
+    case 'reporting': return 'i-lucide-file-text'
+    case 'completed': return 'i-lucide-check-circle'
+    default: return 'i-lucide-circle'
+  }
+}
+
+function formatDate(dateStr: string): string {
+  return new Date(dateStr).toLocaleDateString('fr-FR', {
+    day: 'numeric',
+    month: 'long',
+    year: 'numeric',
+  })
+}
+</script>
+
+<template>
+  <div>
+    <div v-if="sortedSteps.length === 0" class="text-center py-8">
+      <UIcon name="i-lucide-list-checks" class="text-4xl text-gray-400 mb-3" />
+      <p class="text-gray-500">Aucune etape definie pour ce mandat</p>
+    </div>
+
+    <div v-else class="relative">
+      <!-- Timeline line -->
+      <div class="absolute left-4 top-0 bottom-0 w-0.5 bg-gray-200 dark:bg-gray-700" />
+
+      <!-- Steps -->
+      <div class="space-y-4">
+        <div
+          v-for="step in sortedSteps"
+          :key="step.id"
+          class="relative pl-12"
+        >
+          <!-- Timeline dot -->
+          <div
+            class="absolute left-2 w-5 h-5 rounded-full border-2 flex items-center justify-center"
+            :class="{
+              'bg-green-500 border-green-500': step.status === 'completed',
+              'bg-primary border-primary': step.status === 'active' || step.status === 'in_progress',
+              'bg-yellow-400 border-yellow-400': step.status === 'pending',
+              'bg-red-500 border-red-500': step.status === 'revoked',
+              'bg-white dark:bg-gray-900 border-gray-300 dark:border-gray-600': step.status === 'draft',
+            }"
+          >
+            <UIcon
+              v-if="step.status === 'completed'"
+              name="i-lucide-check"
+              class="text-white text-xs"
+            />
+            <UIcon
+              v-else-if="step.status === 'revoked'"
+              name="i-lucide-x"
+              class="text-white text-xs"
+            />
+          </div>
+
+          <UCard>
+            <div class="space-y-2">
+              <div class="flex items-center justify-between">
+                <div class="flex items-center gap-2">
+                  <UIcon :name="stepTypeIcon(step.step_type)" class="text-gray-500" />
+                  <span class="text-sm font-mono text-gray-400">Etape {{ step.step_order }}</span>
+                  <UBadge variant="subtle" color="neutral" size="xs">
+                    {{ stepTypeLabel(step.step_type) }}
+                  </UBadge>
+                </div>
+                <CommonStatusBadge :status="step.status" type="mandate" />
+              </div>
+
+              <h3 v-if="step.title" class="font-medium text-gray-900 dark:text-white">
+                {{ step.title }}
+              </h3>
+
+              <p v-if="step.description" class="text-sm text-gray-600 dark:text-gray-400">
+                {{ step.description }}
+              </p>
+
+              <div class="text-xs text-gray-500">
+                Cree le {{ formatDate(step.created_at) }}
+              </div>
+
+              <div v-if="step.outcome" class="flex items-center gap-2 mt-2">
+                <UIcon name="i-lucide-flag" class="text-gray-400" />
+                <span class="text-sm text-gray-600 dark:text-gray-400">
+                  Resultat : {{ step.outcome }}
+                </span>
+              </div>
+
+              <div v-if="step.vote_session_id" class="mt-2">
+                <UButton
+                  size="xs"
+                  variant="soft"
+                  color="primary"
+                  icon="i-lucide-vote"
+                  label="Voir la session de vote"
+                />
+              </div>
+            </div>
+          </UCard>
+        </div>
+      </div>
+    </div>
+  </div>
+</template>