feat: per-class exemplar preview, class hide toggle, container NMS flag (REQ-182, REQ-183, REQ-184)

frontend/src/pages/ReviewPage.jsx

@@ -23,6 +23,7 @@ export default function ReviewPage({ batchId: rawBatchId, projectId, onProject }
   const [busy, setBusy] = useState(false)
   const [error, setError] = useState('')
   const [activeJob, setActiveJob] = useState(null)
+  const [hiddenClasses, setHiddenClasses] = useState(() => new Set())
 
   const batchId = batch?.id || rawBatchId
   const stripRef = useRef(null)
@@ -184,7 +185,33 @@ export default function ReviewPage({ batchId: rawBatchId, projectId, onProject }
     })
   }, [])
 
-  const markAll = useCallback(() => setMarkedIds(annotations.map((row) => row.id)), [annotations])
+  const toggleHide = useCallback((classId) => {
+    setHiddenClasses((current) => {
+      const next = new Set(current)
+      if (next.has(classId)) next.delete(classId)
+      else next.add(classId)
+      return next
+    })
+  }, [])
+
+  // REQ-183: while a class is hidden, no shape of it may be selected or
+  // marked — however it got there (draw, reclass, copy) — so Delete can
+  // never hit an invisible shape.
+  useEffect(() => {
+    if (!hiddenClasses.size) return
+    setSelectedId((currentId) => {
+      const row = annotations.find((a) => a.id === currentId)
+      return row && hiddenClasses.has(row.class_id) ? null : currentId
+    })
+    setMarkedIds((rows) => rows.filter((id) => {
+      const row = annotations.find((a) => a.id === id)
+      return !row || !hiddenClasses.has(row.class_id)
+    }))
+  }, [hiddenClasses, annotations])
+
+  const visibleAnnotations = annotations.filter((row) => !hiddenClasses.has(row.class_id))
+
+  const markAll = useCallback(() => setMarkedIds(visibleAnnotations.map((row) => row.id)), [visibleAnnotations])
 
   const removeMarked = useCallback(async () => {
     if (!markedIds.length || !frame) return
@@ -460,7 +487,7 @@ export default function ReviewPage({ batchId: rawBatchId, projectId, onProject }
             <AnnotationCanvas
               frame={frame}
               imageUrl={api.frameUrl(frame.id)}
-              annotations={annotations}
+              annotations={visibleAnnotations}
               selectedId={selectedId}
               activeClass={activeClass}
               assistMode={assistMode}
@@ -503,9 +530,9 @@ export default function ReviewPage({ batchId: rawBatchId, projectId, onProject }
                   className="btn"
                   style={{ padding: '2px 8px', fontSize: '0.78rem' }}
                   onClick={markAll}
-                  disabled={!annotations.length}
+                  disabled={!visibleAnnotations.length}
                 >
-                  Select all ({annotations.length})
+                  Select all ({visibleAnnotations.length})
                 </button>
                 <span className="muted" style={{ fontSize: '0.78rem' }}>
                   {markedIds.length
@@ -623,6 +650,8 @@ export default function ReviewPage({ batchId: rawBatchId, projectId, onProject }
           reclass={reclass}
           clearClassInBatch={clearClassInBatch}
           clearClassInFrame={clearClassInFrame}
+          hiddenClasses={hiddenClasses}
+          onToggleHide={toggleHide}
           annotations={annotations}
           selectedId={selectedId}
           setSelectedId={setSelectedId}