feat(02-02): PostCard regen button with inline form, topic override, and regenerated badge

- Add handleRegen function with topic/notes override support
- Add inline popover form with optional topic and notes fields
- Add isRegenerated prop with amber RefreshCw badge for regenerated posts
- Regen button positioned in card header next to expand/collapse chevron
- Form appears below header with Rigenera/Annulla actions

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

frontend/src/components/PostCard.tsx

@@ -26,6 +26,8 @@ interface PostCardProps {
   onRegenerated: (updated: PostResult) => void
   /** Callback quando le slide vengono modificate inline */
   onEdit: (updated: PostResult) => void
+  /** True se questo post è stato rigenerato (non originale) */
+  isRegenerated?: boolean
 }
 
 export function PostCard({
@@ -35,13 +37,40 @@ export function PostCard({
   tono,
   onRegenerated,
   onEdit,
+  isRegenerated,
 }: PostCardProps) {
   const [expanded, setExpanded] = useState(false)
+  const [showRegenForm, setShowRegenForm] = useState(false)
+  const [regenTopic, setRegenTopic] = useState('')
+  const [regenNotes, setRegenNotes] = useState('')
   const generateSingle = useGenerateSingle()
 
   const slot = result.slot
   const post = result.post
 
+  async function handleRegen() {
+    if (!slot) return
+    // Se l'utente ha specificato un topic, usalo come override
+    const overriddenSlot = regenTopic.trim()
+      ? { ...slot, topic: regenTopic.trim() }
+      : slot
+    const req: GenerateRequest = {
+      slot: overriddenSlot,
+      obiettivo_campagna: obiettivoCampagna,
+      brand_name: brandName,
+      tono: regenNotes.trim() || tono, // Se note fornite, usale come tono override
+    }
+    try {
+      const newResult = await generateSingle.mutateAsync(req)
+      onRegenerated({ ...newResult, slot })
+      setShowRegenForm(false)
+      setRegenTopic('')
+      setRegenNotes('')
+    } catch {
+      // Errore gestito da generateSingle.error
+    }
+  }
+
   async function handleRetry() {
     if (!slot) return
     const req: GenerateRequest = {
@@ -123,17 +152,22 @@ export function PostCard({
       ].join(' ')}
     >
       {/* Header card — sempre visibile, click per espandere */}
-      <button
-        onClick={() => setExpanded((v) => !v)}
-        className="w-full px-4 py-4 text-left"
-      >
+      <div className="w-full px-4 py-4 text-left">
         <div className="flex items-start justify-between gap-2">
-          <div className="flex-1 min-w-0">
-            {/* Numero slot + badge */}
+          <div
+            className="flex-1 min-w-0 cursor-pointer"
+            onClick={() => setExpanded((v) => !v)}
+          >
+            {/* Numero slot + badge rigenerato + badge PN/Schwartz */}
             <div className="flex flex-wrap items-center gap-1.5 mb-2">
               <span className="text-xs font-mono text-stone-500">
                 #{result.slot_index + 1}
               </span>
+              {isRegenerated && (
+                <span className="text-amber-400" title="Post rigenerato">
+                  <RefreshCw size={12} />
+                </span>
+              )}
               {slot && (
                 <>
                   <BadgePN tipo={slot.tipo_contenuto} />
@@ -159,12 +193,84 @@ export function PostCard({
             )}
           </div>
 
-          {/* Expand/collapse icon */}
-          <span className="text-stone-500 flex-shrink-0 mt-0.5">
+          {/* Rigenera button + Expand/collapse icon */}
+          <div className="flex items-center gap-1.5 flex-shrink-0 mt-0.5">
+            <button
+              onClick={(e) => {
+                e.stopPropagation()
+                setShowRegenForm((v) => !v)
+              }}
+              className="text-stone-500 hover:text-amber-400 transition-colors"
+              title="Rigenera questo post"
+            >
+              <RefreshCw size={14} />
+            </button>
+            <span
+              className="text-stone-500 cursor-pointer"
+              onClick={() => setExpanded((v) => !v)}
+            >
               {expanded ? <ChevronUp size={16} /> : <ChevronDown size={16} />}
             </span>
           </div>
+        </div>
+      </div>
+
+      {/* Regen inline form */}
+      {showRegenForm && (
+        <div className="px-4 pb-3 border-t border-stone-700/50 pt-3 space-y-3">
+          <div>
+            <label className="text-xs text-stone-400 block mb-1">
+              Topic alternativo <span className="text-stone-600">(opzionale)</span>
+            </label>
+            <input
+              type="text"
+              value={regenTopic}
+              onChange={(e) => setRegenTopic(e.target.value)}
+              placeholder="Es: 3 errori comuni nel marketing digitale"
+              className="w-full px-3 py-2 rounded-lg bg-stone-900 border border-stone-700 text-sm text-stone-200 placeholder:text-stone-600 focus:border-amber-500/50 focus:outline-none"
+            />
+          </div>
+          <div>
+            <label className="text-xs text-stone-400 block mb-1">
+              Note aggiuntive <span className="text-stone-600">(opzionale)</span>
+            </label>
+            <input
+              type="text"
+              value={regenNotes}
+              onChange={(e) => setRegenNotes(e.target.value)}
+              placeholder="Es: tono piu' provocatorio, focus su ROI"
+              className="w-full px-3 py-2 rounded-lg bg-stone-900 border border-stone-700 text-sm text-stone-200 placeholder:text-stone-600 focus:border-amber-500/50 focus:outline-none"
+            />
+          </div>
+          <div className="flex items-center gap-2">
+            <button
+              onClick={handleRegen}
+              disabled={generateSingle.isPending}
+              className="flex items-center gap-1.5 px-3 py-1.5 rounded-lg bg-amber-500 text-stone-950 text-xs font-semibold hover:bg-amber-400 disabled:opacity-50 transition-colors"
+            >
+              {generateSingle.isPending ? (
+                <Loader2 size={12} className="animate-spin" />
+              ) : (
+                <RefreshCw size={12} />
+              )}
+              {generateSingle.isPending ? 'Rigenerazione...' : 'Rigenera'}
             </button>
+            <button
+              onClick={() => {
+                setShowRegenForm(false)
+                setRegenTopic('')
+                setRegenNotes('')
+              }}
+              className="px-3 py-1.5 rounded-lg text-xs text-stone-400 hover:text-stone-200 transition-colors"
+            >
+              Annulla
+            </button>
+          </div>
+          {generateSingle.error && (
+            <p className="text-xs text-red-400">{generateSingle.error.message}</p>
+          )}
+        </div>
+      )}
 
       {/* Expanded: SlideViewer */}
       {expanded && (