fix: bug fixes, test coverage, and CI workflow

- Fix Nodes.First() panic on empty slice (return nil)
- Fix ticker leak in archive.go (create once, defer Stop)
- Fix cookie path matching for empty and root paths
- Fix lost query params in google.go (u.Query().Set was discarded)
- Fix type assertion panic in useragents.go
- Fix dropped date parse error in powerball.go
- Remove unreachable dead code in megamillions.go and powerball.go
- Simplify document.go WaitForNetworkIdle, remove unused root field
- Remove debug fmt.Println calls across codebase
- Replace panic(err) with stderr+exit in all cmd/ programs
- Fix duckduckgo cmd: remove useless defer, return error on bad safesearch
- Fix archive cmd: ToConfig returns error instead of panicking
- Add 39+ unit tests across 6 new test files
- Add Gitea Actions CI workflow (build, test, vet in parallel)

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

sites/powerball/powerball.go

@@ -41,9 +41,20 @@ func deferClose(cl io.Closer) {
 func getDrawing(_ context.Context, doc extractor.Document) (*Drawing, error) {
 	var drawing Drawing
 
-	dateStr, err := doc.SelectFirst("#numbers .title-date").Text()
+	dateNode := doc.SelectFirst("#numbers .title-date")
+	if dateNode == nil {
+		return nil, fmt.Errorf("failed to find date element")
+	}
+
+	dateStr, err := dateNode.Text()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get date text: %w", err)
+	}
 
 	drawing.Date, err = time.Parse("Mon, Jan 2, 2006", dateStr)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse date %q: %w", dateStr, err)
+	}
 
 	nums := doc.Select("div.game-ball-group div.white-balls")
 
@@ -165,22 +176,12 @@ func getNextDrawing(_ context.Context, doc extractor.Document) (*NextDrawing, er
 
 	numeric := numericOnly(txt)
 
-	set := false
 	if strings.Contains(txt, "Billion") {
-		amt := numeric * 1000000000
-		nextDrawing.JackpotDollars = int(amt)
-		set = true
+		nextDrawing.JackpotDollars = int(numeric * 1000000000)
 	} else if strings.Contains(txt, "Million") {
-		amt := numeric * 1000000
-		nextDrawing.JackpotDollars = int(amt)
-		set = true
+		nextDrawing.JackpotDollars = int(numeric * 1000000)
 	} else {
 		nextDrawing.JackpotDollars = int(numeric)
-		set = true
-	}
-
-	if !set {
-		return nil, fmt.Errorf("failed to convert jackpot to currency: %w", err)
 	}
 
 	return &nextDrawing, nil