Add copywrite statements and LICENSE

.copywrite.hcl

@@ -0,0 +1,15 @@
+schema_version = 1
+
+project {
+  license        = "GPL-3.0-or-later"
+  copyright_year = 2026
+  copyright_holder = "Carl Philipp Klemm"
+
+  # (OPTIONAL) A list of globs that should not have copyright/license headers.
+  # Supports doublestar glob patterns for more flexibility in defining which
+  # files or folders should be ignored
+  header_ignore = [
+    # "vendor/**",
+    # "**autogen**",
+  ]
+}