BLD: Add Android support

[mhsmith]

I'm currently targeting the 2.3.x branch as part of a project I'm working on, but I'll rebase this PR on main once it's complete.

• Requires Android improvements needed for building NumPy and related packages pypa/cibuildwheel#2695
• Requires Add support for targeting Android mesonbuild/meson-python#824
• Requires BLD: Add Android support numpy/numpy#30412

• [N/A] closes #xxxx (Replace xxxx with the GitHub issue number)
• Tests added and passed if fixing a bug or adding a new feature
• All code checks passed.
• Added type annotations to new arguments/methods/functions.
• Added an entry in the latest doc/source/whatsnew/vX.X.X.rst file if fixing a bug or adding a new feature.
• [N/A] If I used AI to develop this pull request, I prompted it to follow AGENTS.md.

[mhsmith]

The wheels here were built using the same procedure as numpy/numpy#30412 (comment), with the following changes:

• Set the environment variable PIP_EXTRA_INDEX_URL=https://chaquo.com/pypi-test, so it can find the Android NumPy wheels.
• python/cpython#142912 affects this package more severely, preventing the test suite from even starting. Use CIBW_TEST_SKIP="*" to disable the test suite for now.
• Set CIBW_BEFORE_BUILD="" to prevent the wheels getting a "dirty" marker because of the LICENSE file modification in cibw_before_build.sh.

These wheels pass the Chaquopy smoke tests with the help of this workaround.

When running the full test suite manually, there are a number of failures which I'm looking into. The default 2 GB emulator RAM is also insufficient, so I'll increase that to 4 GB (python/cpython#144418).