feat(11-02): add useReorderCandidates hook, candidateViewMode, and CandidateListItem component

- Add useReorderCandidates mutation hook with apiPatch to /candidates/reorder endpoint
- Add candidateViewMode (list|grid) state and setCandidateViewMode to uiStore
- Create CandidateListItem component with drag handle, rank badge, horizontal layout
- Export RankBadge helper (gold/silver/bronze medal icons for top 3)
- Add style prop support to LucideIcon component
- Add pros/cons fields to CandidateWithCategory in useThreads.ts

src/client/stores/uiStore.ts

@@ -48,6 +48,10 @@ interface UIState {
 	externalLinkUrl: string | null;
 	openExternalLink: (url: string) => void;
 	closeExternalLink: () => void;
+
+	// Candidate view mode
+	candidateViewMode: "list" | "grid";
+	setCandidateViewMode: (mode: "list" | "grid") => void;
 }
 
 export const useUIStore = create<UIState>((set) => ({
@@ -103,4 +107,8 @@ export const useUIStore = create<UIState>((set) => ({
 	externalLinkUrl: null,
 	openExternalLink: (url) => set({ externalLinkUrl: url }),
 	closeExternalLink: () => set({ externalLinkUrl: null }),
+
+	// Candidate view mode
+	candidateViewMode: "list",
+	setCandidateViewMode: (mode) => set({ candidateViewMode: mode }),
 }));