Add BSD-3-Clause LICENSE and pandas attribution

LICENSE

@@ -0,0 +1,36 @@
+BSD 3-Clause License
+
+Copyright (c) 2025-present, GitHub, Inc. and tsessebe (tsb) contributors.
+All rights reserved.
+
+This project is a clean-room TypeScript reimplementation inspired by the
+pandas library (https://github.com/pandas-dev/pandas), and contains some
+files (notably tests) that are derived from pandas. Those portions remain
+under their original BSD 3-Clause License — see the THIRD_PARTY_LICENSES
+and NOTICE files distributed with this project for the full upstream
+copyright notice and attribution.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

NOTICE

@@ -0,0 +1,9 @@
+tsessebe (tsb)
+Copyright (c) 2025-present, GitHub, Inc. and tsessebe (tsb) contributors.
+
+This product is a clean-room TypeScript reimplementation inspired by the
+pandas library (https://github.com/pandas-dev/pandas) and includes
+portions (notably tests) derived from pandas. Those portions are
+redistributed under the terms of the BSD 3-Clause License; see
+THIRD_PARTY_LICENSES.md for the full upstream copyright notice and
+license text.

THIRD_PARTY_LICENSES.md

@@ -0,0 +1,54 @@
+# Third-Party Licenses
+
+tsessebe (`tsb`) incorporates or is inspired by code from third-party
+projects. Their original copyright notices and license texts are
+reproduced below, as required by their licenses.
+
+---
+
+## pandas
+
+- Project: https://github.com/pandas-dev/pandas
+- License: BSD 3-Clause License
+
+Some files in this repository — particularly tests under `tests/` and a
+small number of code patterns — are derived from or inspired by pandas.
+Those portions remain under the BSD 3-Clause License reproduced below.
+
+The tsessebe project as a whole is also distributed under the BSD
+3-Clause License (see the top-level `LICENSE` file), which is compatible
+with and preserves attribution to the upstream pandas license.
+
+```
+BSD 3-Clause License
+
+Copyright (c) 2008-2011, AQR Capital Management, LLC, Lambda Foundry, Inc. and PyData Development Team
+All rights reserved.
+
+Copyright (c) 2011-2026, Open source contributors.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+* Redistributions of source code must retain the above copyright notice, this
+  list of conditions and the following disclaimer.
+
+* Redistributions in binary form must reproduce the above copyright notice,
+  this list of conditions and the following disclaimer in the documentation
+  and/or other materials provided with the distribution.
+
+* Neither the name of the copyright holder nor the names of its
+  contributors may be used to endorse or promote products derived from
+  this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+```

package.json

@@ -2,6 +2,7 @@
   "name": "tsb",
   "version": "0.0.1",
   "description": "A TypeScript port of pandas, built from first principles",
+  "license": "BSD-3-Clause",
   "type": "module",
   "main": "./src/index.ts",
   "module": "./src/index.ts",