feat: add top-level persistent filters for keyword research (#93)

* feat: add top-level persistent filters for keyword research

Add a collapsible filter bar below the search bar so users can set
default filters (volume, CPC, difficulty, include/exclude terms) that
persist across searches and sessions via localStorage.

* simplify: remove top-level filter UI, keep only localStorage persistence

Revert the search bar to its original state. The existing in-table
filters already provide good UX — all we needed was persistence.
Auto-expand the filter panel when persisted filters are active on load.

* feat: show filtered keyword count as "Showing X of Y keywords"

When filters are active, display "Showing 14 of 150 keywords" instead
of just "14 keywords". When no filters are active, show "Showing X
keywords". Applied to both desktop and mobile views.

* style: fix prettier formatting

src/client/features/keywords/hooks/useLocalKeywordFilters.ts

@@ -1,17 +1,58 @@
-import { useCallback } from "react";
+import { useCallback, useEffect } from "react";
 import { useForm, useStore } from "@tanstack/react-form";
+import { z } from "zod";
 import {
   EMPTY_FILTERS,
   type KeywordFilterValues,
 } from "@/client/features/keywords/keywordResearchTypes";
 
+const STORAGE_KEY = "keyword-default-filters";
+
+const filterValuesSchema = z.object({
+  include: z.string(),
+  exclude: z.string(),
+  minVol: z.string(),
+  maxVol: z.string(),
+  minCpc: z.string(),
+  maxCpc: z.string(),
+  minKd: z.string(),
+  maxKd: z.string(),
+});
+
+function loadFiltersFromStorage(): KeywordFilterValues {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY);
+    if (!raw) return EMPTY_FILTERS;
+    return filterValuesSchema.parse(JSON.parse(raw));
+  } catch {
+    return EMPTY_FILTERS;
+  }
+}
+
+function saveFiltersToStorage(filters: KeywordFilterValues) {
+  try {
+    const hasAnyFilter = Object.values(filters).some((v) => v.trim() !== "");
+    if (hasAnyFilter) {
+      localStorage.setItem(STORAGE_KEY, JSON.stringify(filters));
+    } else {
+      localStorage.removeItem(STORAGE_KEY);
+    }
+  } catch {
+    // storage full or unavailable
+  }
+}
+
 export function useLocalKeywordFilters() {
   const filtersForm = useForm({
-    defaultValues: EMPTY_FILTERS,
+    defaultValues: loadFiltersFromStorage(),
   });
 
   const values = useStore(filtersForm.store, (s) => s.values);
 
+  useEffect(() => {
+    saveFiltersToStorage(values);
+  }, [values]);
+
   const resetFilters = useCallback(() => {
     const keys: Array<keyof KeywordFilterValues> = [
       "include",

src/client/features/keywords/page/KeywordResearchDesktopResults.tsx

@@ -103,9 +103,16 @@ function DesktopKeywordPanel({ controller }: Props) {
 }
 
 function DesktopTableCard({ controller }: Props) {
-  const { activeFilterCount, filteredRows, selectedRows, showFilters } =
+  const { activeFilterCount, filteredRows, rows, selectedRows, showFilters } =
     controller;
 
+  const keywordCountLabel =
+    selectedRows.size > 0
+      ? `${selectedRows.size} of ${filteredRows.length} selected`
+      : activeFilterCount > 0
+        ? `Showing ${filteredRows.length} of ${rows.length} keywords`
+        : `Showing ${filteredRows.length} keywords`;
+
   return (
     <div className="flex-1 flex flex-col min-w-0 border border-base-300 rounded-xl bg-base-100 overflow-hidden">
       <div className="shrink-0 flex items-center gap-2 px-4 py-2 border-b border-base-300">
@@ -123,9 +130,7 @@ function DesktopTableCard({ controller }: Props) {
           ) : null}
         </button>
         <span className="text-sm text-base-content/60">
-          {selectedRows.size > 0
-            ? `${selectedRows.size} of ${filteredRows.length} selected`
-            : `${filteredRows.length} keywords`}
+          {keywordCountLabel}
         </span>
         <div className="flex-1" />
         <button

src/client/features/keywords/page/KeywordResearchMobileResults.tsx

@@ -58,9 +58,16 @@ export function KeywordResearchMobileResults({ controller }: Props) {
 }
 
 function MobileKeywordCards({ controller }: Props) {
-  const { activeFilterCount, filteredRows, selectedRows, showFilters } =
+  const { activeFilterCount, filteredRows, rows, selectedRows, showFilters } =
     controller;
 
+  const keywordCountLabel =
+    selectedRows.size > 0
+      ? `${selectedRows.size} selected`
+      : activeFilterCount > 0
+        ? `Showing ${filteredRows.length} of ${rows.length}`
+        : `Showing ${filteredRows.length} keywords`;
+
   return (
     <div className="flex-1 flex flex-col overflow-hidden">
       {controller.showApproximateMatchNotice ? (
@@ -88,9 +95,7 @@ function MobileKeywordCards({ controller }: Props) {
           ) : null}
         </button>
         <span className="text-xs text-base-content/60">
-          {selectedRows.size > 0
-            ? `${selectedRows.size} selected`
-            : `${filteredRows.length} keywords`}
+          {keywordCountLabel}
         </span>
         <div className="flex-1" />
         <button

src/client/features/keywords/state/keywordControllerInternals.ts

@@ -20,8 +20,8 @@ export function useResolvedKeywordLocation(
   return { locationCode, setPreferredLocationCode };
 }
 
-export function useKeywordUiState() {
-  const [showFilters, setShowFilters] = useState(false);
+export function useKeywordUiState(initialShowFilters: boolean) {
+  const [showFilters, setShowFilters] = useState(initialShowFilters);
   const [selectedKeyword, setSelectedKeyword] =
     useState<KeywordResearchRow | null>(null);
   const [showSaveDialog, setShowSaveDialog] = useState(false);

src/client/features/keywords/state/useKeywordResearchController.ts

@@ -160,7 +160,6 @@ export function useKeywordResearchController(
 }
 
 function useKeywordControllerState(input: KeywordResearchControllerInput) {
-  const uiState = useKeywordUiState();
   const { locationCode, setPreferredLocationCode } =
     useResolvedKeywordLocation(input);
   const {
@@ -168,6 +167,9 @@ function useKeywordControllerState(input: KeywordResearchControllerInput) {
     values: filterValues,
     resetFilters,
   } = useLocalKeywordFilters();
+  const uiState = useKeywordUiState(
+    Object.values(filterValues).some((v) => v.trim() !== ""),
+  );
   const { selectedRows, clearSelection, toggleRowSelection, toggleAllRows } =
     useKeywordSelection();
   const {