feat(ui): mobile-responsive sidebar + rules improvements

- Sidebar: hidden on mobile, opens as slide-out drawer with hamburger
  toggle; auto-closes on navigation; desktop layout unchanged
- Layout: responsive padding accounting for mobile header bar
- Rules: add tag as a condition field (has/not-has tag)
- Rules: apply a single rule via per-rule Apply button
- Rules: splits-from defaults to 2026-01-09

src/lib/hooks.ts

@@ -511,11 +511,11 @@ export function useDeleteRule() {
 export function useApplyRules() {
   const qc = useQueryClient();
   return useMutation({
-    mutationFn: async (splitFrom?: string) => {
+    mutationFn: async (args?: { splitFrom?: string; ruleId?: number }) => {
       const res = await fetch("/api/rules/apply", {
         method: "POST",
         headers: { "Content-Type": "application/json" },
-        body: JSON.stringify({ splitFrom: splitFrom || null }),
+        body: JSON.stringify({ splitFrom: args?.splitFrom || null, ruleId: args?.ruleId || null }),
       });
       if (!res.ok) throw new Error("Failed to apply rules");
       return res.json() as Promise<{ id: number; matched: number; transactions_affected: number }>;