Re-enable libtiledb grafting with auditwheel

[ktsitsi]

This PR:

• Changes the build process to install libtiledb core library on an external destination and outside the wheel. This allows auditwheel to pick it up as an external dependency and graft it.
• Requires fixes on the test_sdist step as it fails. This requires further investigation as the built wheels have been installed on local/machines and EC2 instances and the tests run successfully during the build stage. https://github.com/TileDB-Inc/TileDB-Py/actions/runs/17504381704/job/49724678086#step:4:6929
• The structure of the wheel is the following after the changes for UNIX:

konstantinostsitsimpikos@Konstantinoss-MacBook-Pro-3 deleteme % ls -l
total 35328
drwxr-xr-x@ 33 konstantinostsitsimpikos  staff      1056 Sep  4  2025 examples
drwxr-xr-x@  5 konstantinostsitsimpikos  staff       160 Sep  4  2025 external
drwxr-xr-x@ 58 konstantinostsitsimpikos  staff      1856 Sep  4  2025 tiledb
-rw-r--r--@  1 konstantinostsitsimpikos  staff  18085008 Sep  4  2025 tiledb-0.34.2-cp310-cp310-manylinux_2_28_x86_64.whl
drwxr-xr-x@  6 konstantinostsitsimpikos  staff       192 Sep  4  2025 tiledb-0.34.2.dist-info
drwxr-xr-x@  3 konstantinostsitsimpikos  staff        96 Sep  4  2025 tiledb.libs
konstantinostsitsimpikos@Konstantinoss-MacBook-Pro-3 deleteme % cd tiledb.libs 
konstantinostsitsimpikos@Konstantinoss-MacBook-Pro-3 tiledb.libs % ls
libtiledb-37432e17.so.2.28

So the libtitledb library is being grafted with a 37432e17 hash.

REMARKS:

• The build process follows two different paths depending on whether or not we build our wheels on CI utilizing cibuildwheel -> auditwheel or building the wheel through the source distribution files.

Closes CORE-332

[ktsitsi]

@kounelisagis @ihnorton could you take a look on the test_sdist that fails even though the build tests are succeeding and the wheel is being built. I tested the wheels on EC2 instances and the tests runs just fine there after the installation.
https://github.com/TileDB-Inc/TileDB-Py/actions/runs/17504381704

[ihnorton]

could you take a look on the test_sdist

The changeset here should only be applied when we are doing a CI build: https://github.com/TileDB-Inc/TileDB-Py/pull/2238/files#diff-64e075a38340d9989b5b947d543f08464f279b09f838b898dc5bf5a887b64603L46-R51

Otherwise when building from the sdist, the resulting (locally-built) wheel will only have the hardcoded tiledb-external RPATH (which doesn't exist).

[jp-dark]

Thank you!

[ktsitsi]

@ihnorton @kounelisagis Would you like to make a final check before we merge?

[kounelisagis]

I did a quick pass. The changes seem reasonable but, please, give me 1 more day.

[kounelisagis]

Testing locally on macos and ubuntu, it all LGTM. Thanks!!!