feat: Phase 2 card interactions - priority picker, context menu, WIP limits, column collapse, checklist reorder

- PriorityPicker component with 5 colored chips in card detail modal
- Card context menu: Move to column, Set priority, Duplicate, Delete
- duplicateCard store action (clones card, inserts after original)
- Column WIP limits with amber/red indicators when at/over limit
- Column collapse/expand to 40px vertical strip
- Checklist item drag reordering with grip handle
- Comment store actions (addComment, deleteComment) for Phase 3

src/stores/board-store.ts

@@ -28,10 +28,13 @@ interface BoardActions {
   moveColumn: (fromIndex: number, toIndex: number) => void;
   setColumnWidth: (columnId: string, width: ColumnWidth) => void;
   setColumnColor: (columnId: string, color: string | null) => void;
+  setColumnWipLimit: (columnId: string, limit: number | null) => void;
+  toggleColumnCollapse: (columnId: string) => void;
 
   addCard: (columnId: string, title: string) => string;
   updateCard: (cardId: string, updates: Partial<Card>) => void;
   deleteCard: (cardId: string) => void;
+  duplicateCard: (cardId: string) => string | null;
   moveCard: (
     cardId: string,
     fromColumnId: string,
@@ -48,10 +51,14 @@ interface BoardActions {
   toggleChecklistItem: (cardId: string, itemId: string) => void;
   updateChecklistItem: (cardId: string, itemId: string, text: string) => void;
   deleteChecklistItem: (cardId: string, itemId: string) => void;
+  reorderChecklistItems: (cardId: string, fromIndex: number, toIndex: number) => void;
 
   addAttachment: (cardId: string, attachment: Omit<Attachment, "id">) => void;
   removeAttachment: (cardId: string, attachmentId: string) => void;
 
+  addComment: (cardId: string, text: string) => void;
+  deleteComment: (cardId: string, commentId: string) => void;
+
   updateBoardTitle: (title: string) => void;
   updateBoardColor: (color: string) => void;
   updateBoardSettings: (settings: Board["settings"]) => void;
@@ -195,6 +202,26 @@ export const useBoardStore = create<BoardState & BoardActions>()(
         }));
       },
 
+      setColumnWipLimit: (columnId, limit) => {
+        mutate(get, set, (b) => ({
+          ...b,
+          updatedAt: now(),
+          columns: b.columns.map((c) =>
+            c.id === columnId ? { ...c, wipLimit: limit } : c
+          ),
+        }));
+      },
+
+      toggleColumnCollapse: (columnId) => {
+        mutate(get, set, (b) => ({
+          ...b,
+          updatedAt: now(),
+          columns: b.columns.map((c) =>
+            c.id === columnId ? { ...c, collapsed: !c.collapsed } : c
+          ),
+        }));
+      },
+
       // -- Card actions --
 
       addCard: (columnId, title) => {
@@ -260,6 +287,48 @@ export const useBoardStore = create<BoardState & BoardActions>()(
         });
       },
 
+      duplicateCard: (cardId) => {
+        const { board } = get();
+        if (!board) return null;
+        const original = board.cards[cardId];
+        if (!original) return null;
+        const column = board.columns.find((c) => c.cardIds.includes(cardId));
+        if (!column) return null;
+
+        const newId = ulid();
+        const ts = now();
+        const clone: Card = {
+          ...original,
+          id: newId,
+          title: `${original.title} (copy)`,
+          comments: [],
+          createdAt: ts,
+          updatedAt: ts,
+        };
+
+        const insertIndex = column.cardIds.indexOf(cardId) + 1;
+
+        mutate(get, set, (b) => ({
+          ...b,
+          updatedAt: ts,
+          cards: { ...b.cards, [newId]: clone },
+          columns: b.columns.map((c) =>
+            c.id === column.id
+              ? {
+                  ...c,
+                  cardIds: [
+                    ...c.cardIds.slice(0, insertIndex),
+                    newId,
+                    ...c.cardIds.slice(insertIndex),
+                  ],
+                }
+              : c
+          ),
+        }));
+
+        return newId;
+      },
+
       moveCard: (cardId, fromColumnId, toColumnId, toIndex) => {
         mutate(get, set, (b) => ({
           ...b,
@@ -428,6 +497,24 @@ export const useBoardStore = create<BoardState & BoardActions>()(
         });
       },
 
+      reorderChecklistItems: (cardId, fromIndex, toIndex) => {
+        mutate(get, set, (b) => {
+          const card = b.cards[cardId];
+          if (!card) return b;
+          const items = [...card.checklist];
+          const [moved] = items.splice(fromIndex, 1);
+          items.splice(toIndex, 0, moved);
+          return {
+            ...b,
+            updatedAt: now(),
+            cards: {
+              ...b.cards,
+              [cardId]: { ...card, checklist: items, updatedAt: now() },
+            },
+          };
+        });
+      },
+
       // -- Attachment actions --
 
       addAttachment: (cardId, attachment) => {
@@ -473,6 +560,47 @@ export const useBoardStore = create<BoardState & BoardActions>()(
         });
       },
 
+      // -- Comment actions --
+
+      addComment: (cardId, text) => {
+        mutate(get, set, (b) => {
+          const card = b.cards[cardId];
+          if (!card) return b;
+          const comment = { id: ulid(), text, createdAt: now() };
+          return {
+            ...b,
+            updatedAt: now(),
+            cards: {
+              ...b.cards,
+              [cardId]: {
+                ...card,
+                comments: [comment, ...card.comments],
+                updatedAt: now(),
+              },
+            },
+          };
+        });
+      },
+
+      deleteComment: (cardId, commentId) => {
+        mutate(get, set, (b) => {
+          const card = b.cards[cardId];
+          if (!card) return b;
+          return {
+            ...b,
+            updatedAt: now(),
+            cards: {
+              ...b.cards,
+              [cardId]: {
+                ...card,
+                comments: card.comments.filter((c) => c.id !== commentId),
+                updatedAt: now(),
+              },
+            },
+          };
+        });
+      },
+
       // -- Board metadata --
 
       updateBoardTitle: (title) => {