chore: add license header in rust src

Author: daniqss

src/generate.rs

@@ -1,3 +1,19 @@
+// stepcode: specialized tool for generating static books with interactive pseudocode.
+// Copyright (C) 2026  stepcode authors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 use crate::tree::{DirNode, FileNode, Node};
 use std::fs;
 use std::path::Path;

src/main.rs

@@ -1,3 +1,19 @@
+// stepcode: specialized tool for generating static books with interactive pseudocode.
+// Copyright (C) 2026  stepcode authors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 pub mod generate;
 pub mod parse;
 pub mod tree;

src/parse.rs

@@ -1,3 +1,19 @@
+// stepcode: specialized tool for generating static books with interactive pseudocode.
+// Copyright (C) 2026  stepcode authors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 use pulldown_cmark::{Parser, html};
 use serde::Deserialize;
 use std::collections::HashMap;

src/tree.rs

@@ -1,3 +1,19 @@
+// stepcode: specialized tool for generating static books with interactive pseudocode.
+// Copyright (C) 2026  stepcode authors
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 use crate::parse::{Config, Frontmatter, parse_markdown};
 use std::fs;
 use std::path::Path;