Naming, layout and comments: descriptive full-word names, one item per line in wrapped calls and literals, and doc comments on exported names

Short and single-letter names in application code become full words (tests
keep theirs). Wrapped calls, signatures and composite literals put one item
per line, and one-line function bodies are expanded. Exported names and
groups of constants get doc comments, and comments refer to the renamed
identifiers.

internal/fetcher/fetcher_test.go

@@ -77,7 +77,9 @@ func TestFetchFunctions(t *testing.T) {
 			"releases found",
 			http.StatusOK,
 			onePackage,
-			func(err error) bool { return err == nil },
+			func(err error) bool {
+				return err == nil
+			},
 			"nil",
 		},
 		{"no releases", http.StatusOK, emptyPackage, func(err error) bool {
@@ -92,7 +94,10 @@ func TestFetchFunctions(t *testing.T) {
 			t.Run(fname+"/"+tc.name, func(t *testing.T) {
 				srv, hits := ftsServer(t, tc.status, tc.body)
 				err := fetch(
-					context.Background(), slog.Default(), confFor(srv.URL), time.Now().Add(-time.Hour),
+					context.Background(),
+					slog.Default(),
+					confFor(srv.URL),
+					time.Now().Add(-time.Hour),
 				)
 				if !tc.check(err) {
 					t.Fatalf("err = %v, want %s", err, tc.wantErr)
@@ -204,7 +209,9 @@ func TestRunLogsSourceErrors(t *testing.T) {
 	var buf bytes.Buffer
 	def := slog.Default()
 	slog.SetDefault(slog.New(slog.NewTextHandler(&buf, nil)))
-	t.Cleanup(func() { slog.SetDefault(def) })
+	t.Cleanup(func() {
+		slog.SetDefault(def)
+	})
 
 	// A zero interval makes each worker fail straight away.
 	conf := &config.JobSearchConfig{}
@@ -253,7 +260,9 @@ func TestRunShutsDownOnWorkerError(t *testing.T) {
 	conf.Sources.Sleeper.Enabled = true
 
 	done := make(chan error, 1)
-	go func() { done <- Run(context.Background(), conf, time.Now().Add(-time.Hour)) }()
+	go func() {
+		done <- Run(context.Background(), conf, time.Now().Add(-time.Hour))
+	}()
 
 	select {
 	case err := <-done: