Lots of features, first version that reliably crawls Geminispace.

- [x] Concurrent downloading with workers
- [x] Concurrent connection limit per host
- [x] URL Blacklist
- [x] Save image/* and text/* files
- [x] Configuration via environment variables
- [x] Storing snapshots in PostgreSQL
- [x] Proper response header & body UTF-8 and format validation
.

.

gemini/processing_test.go

@@ -0,0 +1,13 @@
+package gemini
+
+import "testing"
+
+// Make sure NULL bytes are removed
+func TestEnsureValidUTF8(t *testing.T) {
+	// Create a string with a null byte
+	strWithNull := "Hello" + string('\x00') + "world"
+	result, _ := EnsureValidUTF8([]byte(strWithNull))
+	if result != "Helloworld" {
+		t.Errorf("Expected string without NULL byte, got %s", result)
+	}
+}