feat: message parser with json/regex/text modes

internal/parser/text.go

@@ -0,0 +1,11 @@
+package parser
+
+type TextParser struct{}
+
+func (p *TextParser) Parse(body []byte) (*ParsedMessage, error) {
+	return &ParsedMessage{
+		Event: "default", // text mode has no explicit event
+		Data:  map[string]interface{}{"Body": string(body)},
+		Body:  string(body),
+	}, nil
+}