feat(frontend): add three-column results layout with left sidebar navigation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/views/views.go

@@ -50,6 +50,15 @@ type PageData struct {
 	UnresponsiveEngines [][2]string
 	PageNumbers         []PageNumber
 	ShowHeader          bool
+	// New fields for three-column layout
+	Categories         []string
+	CategoryIcons     map[string]string
+	DisabledCategories []string
+	ActiveCategory    string
+	TimeFilters       []FilterOption
+	TypeFilters       []FilterOption
+	ActiveTime        string
+	ActiveType        string
 }
 
 // ResultView is a template-friendly wrapper around a MainResult.
@@ -73,6 +82,12 @@ type InfoboxView struct {
 	ImgSrc  string
 }
 
+// FilterOption represents a filter radio option for the sidebar.
+type FilterOption struct {
+	Label string
+	Value string
+}
+
 var (
 	tmplFull    *template.Template
 	tmplIndex   *template.Template
@@ -116,12 +131,52 @@ func OpenSearchXML(baseURL string) ([]byte, error) {
 }
 
 // FromResponse builds PageData from a search response and request params.
-func FromResponse(resp contracts.SearchResponse, query string, pageno int) PageData {
+func FromResponse(resp contracts.SearchResponse, query string, pageno int, activeCategory, activeTime, activeType string) PageData {
+	// Set defaults
+	if activeCategory == "" {
+		activeCategory = "all"
+	}
+
 	pd := PageData{
 		Query:               query,
 		Pageno:              pageno,
 		NumberOfResults:     resp.NumberOfResults,
 		UnresponsiveEngines: resp.UnresponsiveEngines,
+
+		// New: categories with icons
+		Categories: []string{"all", "news", "images", "videos", "maps"},
+		DisabledCategories: []string{"shopping", "music", "weather"},
+		CategoryIcons: map[string]string{
+			"all":      "🌐",
+			"news":     "📰",
+			"images":   "🖼️",
+			"videos":   "🎬",
+			"maps":     "🗺️",
+			"shopping": "🛒",
+			"music":    "🎵",
+			"weather":  "🌤️",
+		},
+		ActiveCategory: activeCategory,
+
+		// Time filters
+		TimeFilters: []FilterOption{
+			{Label: "Any time", Value: ""},
+			{Label: "Past hour", Value: "h"},
+			{Label: "Past 24 hours", Value: "d"},
+			{Label: "Past week", Value: "w"},
+			{Label: "Past month", Value: "m"},
+			{Label: "Past year", Value: "y"},
+		},
+		ActiveTime: activeTime,
+
+		// Type filters
+		TypeFilters: []FilterOption{
+			{Label: "All results", Value: ""},
+			{Label: "News", Value: "news"},
+			{Label: "Videos", Value: "video"},
+			{Label: "Images", Value: "image"},
+		},
+		ActiveType: activeType,
 	}
 
 	// Convert results.