p1: /v2/scrape, /v1/fetch, auth, CLI, contract tests

Single Fetcher.Fetch on the Guard that holds DenyPrefixes. skipTlsVerification
is ignored. No 502. keys add writes the secret only to --out. Release binary
has no -test-allow-prefix.

vendor/github.com/JohannesKaufmann/html-to-markdown/v2/internal/textutils/quote.go

@@ -0,0 +1,39 @@
+package textutils
+
+import "bytes"
+
+const (
+	DOUBLE_QUOTE = '"'
+	SINGLE_QUOTE = '\''
+)
+
+func SurroundBy(content []byte, chars []byte) []byte {
+	content = append(chars, content...)
+	content = append(content, chars...)
+	return content
+}
+func SurroundByQuotes(content []byte) []byte {
+	if len(content) == 0 {
+		return nil
+	}
+
+	containsDoubleQuote := bytes.ContainsRune(content, DOUBLE_QUOTE)
+	containsSingleQuote := bytes.ContainsRune(content, SINGLE_QUOTE)
+
+	if containsDoubleQuote && containsSingleQuote {
+		// Escape all quotes
+		content = bytes.ReplaceAll(content, []byte(`"`), []byte(`\"`))
+
+		// Surround the content by double quotes
+		return SurroundBy(content, []byte(`"`))
+	}
+	if containsDoubleQuote {
+		// Since it contains double quotes (but no single quotes)
+		// we can surround it by single quotes
+		return SurroundBy(content, []byte(`'`))
+	}
+
+	// It may contain single quotes, but definitely no double quotes,
+	// so we can safely surround it by double quotes.
+	return SurroundBy(content, []byte(`"`))
+}