Move CI to PyPy 3.11, raise minimum Python to 3.11

CI is currently red on every leg. The dependency chain
sqlalchemy-stubs 0.4 -> mypy 2.3.0 -> ast-serialize 0.6.0 (a Rust/PyO3
extension) requires Python >= 3.11, so installation fails outright on
pypy3.9, pypy3.10 and CPython 3.9:

    error: the configured PyPy interpreter version (3.10) is lower than
           PyO3's minimum supported version (3.11)

Raise the floor to 3.11 across the board and move PyPy to 3.11
(PyPy 7.3.23 / Python 3.11.15, released 2026-05-26).

- .github/workflows/python-package.yml: matrix ["3.9", "3.12", "pypy3.9",
  "pypy3.10"] -> ["3.11", "3.12", "pypy3.11"]. Verified that pypy3.11 resolves
  in the PyPy release index that actions/setup-python reads
  (downloads.python.org/pypy/versions.json lists 3.11.15 / 7.3.23 as stable).
- README.md: badge and stated minimum 3.9 -> 3.11; note PyPy 3.11 as the
  supported PyPy version.
- docs/setup_linux.md: install PyPy 3.11; update the download URL to
  pypy3.11-v7.3.23-linux64.tar.gz. Note the archive is now .tar.gz, not the
  .tar.bz2 that older PyPy releases shipped.
- docs/setup_macos.md: PyPy 3.9 -> PyPy 3.11.
- .gitignore: replace the pypy39/pypy310 entries with pypy311.

vectors/ is deliberately untouched. It is a separate CPython environment
(currently 3.9.4, with gensim 3.8.2 from 2019) that the main app's minimum
does not govern, and there is no evidence that stack builds on 3.11. Treat
modernising it as separate work.

Both new URLs verified to return HTTP 200. The shell scripts under scripts/
reference 'venv/' generically and need no change.

Known unrelated failure: tests/test_queries.py::test_currency fails on
CPython 3.12 with dependencies installed successfully, so it is independent
of the interpreter change and will need fixing separately for a fully green
build.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: vthorsteinsson

.github/workflows/python-package.yml

@@ -36,7 +36,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["3.9", "3.12", "pypy3.9", "pypy3.10"]
+        python-version: ["3.11", "3.12", "pypy3.11"]
 
     steps:
     - uses: actions/checkout@v4

.gitignore

@@ -125,8 +125,7 @@ p3*/
 p7*/
 pypy/
 pypy*
-pypy39/*
-pypy310/*
+pypy311/*
 cpython*/
 venv
 p312/*

README.md

@@ -1,5 +1,5 @@
 [![License: GPL v3](https://img.shields.io/badge/License-GPLv3-blue.svg)](https://www.gnu.org/licenses/gpl-3.0)
-[![Python 3.9](https://img.shields.io/badge/python-3.9-blue.svg)](https://www.python.org/downloads/release/python-390/)
+[![Python 3.11](https://img.shields.io/badge/python-3.11-blue.svg)](https://www.python.org/downloads/release/python-3110/)
 [![Build](https://github.com/mideind/Greynir/actions/workflows/python-package.yml/badge.svg)]()
 
 <img src="static/img/greynir-logo-large.png" alt="Greynir" width="200" height="200" align="right" style="margin-left:20px; margin-bottom: 20px;">
@@ -82,8 +82,9 @@ Greynir may in due course be expanded, for instance:
 Greynir is written in [Python 3](https://www.python.org/) except for its core
 Earley-based parser module which is written in C++ and called
 via [CFFI](https://cffi.readthedocs.org/en/latest/index.html).
-Greynir requires Python 3.9 or later, and runs on CPython and
+Greynir requires Python 3.11 or later, and runs on CPython and
 [PyPy](http://pypy.org/), with the latter being recommended for performance reasons.
+PyPy 3.11 is the supported PyPy version.
 
 Greynir works in stages, roughly as follows:
 

docs/setup_linux.md

@@ -50,14 +50,14 @@ Install [git](https://git-scm.com) if it's not already installed:
 sudo apt-get install git
 ```
 
-Install PyPy 3.9 or later ([available here](http://pypy.org/download.html)).
+Install PyPy 3.11 ([available here](http://pypy.org/download.html)).
 For example:
 
 ```bash
 mkdir ~/pypy
 cd ~/pypy
-wget https://downloads.python.org/pypy/pypy3.9-v7.3.12-linux64.tar.bz2
-tar --strip-components=1 -xvf pypy3.9-v7.3.12-linux64.tar.bz2
+wget https://downloads.python.org/pypy/pypy3.11-v7.3.23-linux64.tar.gz
+tar --strip-components=1 -xvf pypy3.11-v7.3.23-linux64.tar.gz
 ```
 
 The PyPy binary should now be installed in `~/pypy/bin/pypy3`.

docs/setup_macos.md

@@ -13,7 +13,7 @@ brew install python3 pypy3 postgresql ossp-uuid
 Alternatively, you can install these packages manually:
 
 * [Python 3](https://www.python.org/downloads/mac-osx/)
-* [PyPy 3.9](https://pypy.org/download.html)
+* [PyPy 3.11](https://pypy.org/download.html)
 * [PostgreSQL](https://www.postgresql.org/download/macosx/)
 * [uuid-ossp module](https://www.postgresql.org/docs/devel/uuid-ossp.html)