Added missing license info. Added notes to readme

Author: kylebme

README.md

@@ -25,3 +25,8 @@ PlotPurr downsamples the input data using Clickhouse and dynamically fetches new
 ## Motivation
 
 Existing plotting GUI tools (PlotJuggler, Rerun) are excellent, but they focus on datasets that can fit in RAM, since they load the entire dataset. Additionally, there is a large set of tooling for dealing with large datasets (Clickhouse, DuckDB, Polars, etc), but they are just the backend. They still require you to write code to get data and plot it. Sometimes you just need to plot something to skim through it before diving deeper in another tool. I wanted a tool that gives you the ease of use of PlotJuggler for large datasets in parquet format.
+
+## Notes
+
+This is a very early project, but it seems to be working ok. Disclaimer: it was mostly written by AI.
+I have mostly tested it with parquet files, so other formats may not work as intended yet.

electron/main.js

@@ -1,3 +1,12 @@
+// Copyright (C) 2025 Kyle Bartholomew
+
+// This file is part of PlotPurr.
+
+// PlotPurr 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.
+
+// PlotPurr 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 PlotPurr. If not, see <https://www.gnu.org/licenses/>. 
+
 const path = require("path");
 const http = require("http");
 const { spawn } = require("child_process");

electron/preload.js

@@ -1,3 +1,12 @@
+// Copyright (C) 2025 Kyle Bartholomew
+
+// This file is part of PlotPurr.
+
+// PlotPurr 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.
+
+// PlotPurr 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 PlotPurr. If not, see <https://www.gnu.org/licenses/>. 
+
 const { contextBridge, ipcRenderer } = require("electron");
 
 contextBridge.exposeInMainWorld("electronAPI", {