This reverts commit 7753f33.

---
TYPE: NO_HISTORY
DESC: Revert "Update libmagic to version 5.45 (#4673)"

This reverts commit 7753f33.

---
TYPE: NO_HISTORY
DESC: Revert "Update libmagic to version 5.45 (#4673)"

This reverts commit 7753f33.

---
TYPE: NO_HISTORY
DESC: Revert "Update libmagic to version 5.45 (#4673)"

…". (#4808) (#4810)

Backport 0ae4818 from #4808

---
TYPE: NO_HISTORY
DESC: Revert "Update libmagic to version 5.45
(#4673)"

Co-authored-by: KiterLuc <[email protected]>

This reverts commit 7753f33.

---
TYPE: NO_HISTORY
DESC: Revert "Update libmagic to version 5.45 (#4673)"

[SC-25167](https://app.shortcut.com/tiledb-inc/story/25167)
[SC-47655](https://app.shortcut.com/tiledb-inc/story/47655)
[SC-47656](https://app.shortcut.com/tiledb-inc/story/47656)
[SC-47657](https://app.shortcut.com/tiledb-inc/story/47657)
[SC-47658](https://app.shortcut.com/tiledb-inc/story/47658)

This PR overhauls the facilities to embed and load the `magic.mgc` file
that is needed by libmagic:

*
The most important change is the removal of
`magic_mgc_gzipped.bin.tar.bz2`. This file contained a copy of
`magic.mgc` that was compressed, converted to escaped C characters,
packed and compressed again to take less space, and stored in source
control, so that at build time to get unpacked and `#include`d in
`mgc_dict.cc`. Because this file was being prepared ahead of time by a
manually invoked C++ program, this approach had the disadvantage that it
tied the Core to a specific version of libmagic. This was made evident
in #4673, where just updating libmagic was not enough; we also had to
update `magic_mgc_gzipped.bin.tar.bz2`.

What we do now is rely on CMake to find `magic.mgc` and perform its
entire preparation at build time. The C++ program was rewritten to be a
CMake script, which makes it much simpler and enables it to run on
cross-compilation scenarios. The script accepts the uncompressed
`magic.mgc` file, compresses it and produces a header file of the
following format:

  ```cpp
  static const unsigned char magic_mgc_compressed_bytes[] = {
  0x28, 0xb5, 0x2f, 0xfd, …
  };
constexpr size_t magic_mgc_compressed_size =
sizeof(magic_mgc_compressed_bytes);
// Editorial note: we used to prepend the decompressed size at the start
of the
// binary blob, but this was non-standard and could not be easily done
by CMake.
  constexpr size_t magic_mgc_decompressed_size = 7041352;
  ```
* The algorithm to compress `magic.mgc` was changed from gzip to zstd,
resulting in a 17.9% reduction of the compressed size (from 333067 το
273500 bytes).
* Tests for `mgc_dict` were also updated to use Catch2, and were wired
to run along with the other standalone unit tests.
* This necessitated to make an object library for `mgc_dict`, which was
done as well.

Validated by successfully running `unit_mgc_dict` locally.

---
TYPE: BUILD
DESC: Improve embedding of `magic.mgc` and allow compiling with any
libmagic version.

[SC-56749](https://app.shortcut.com/tiledb-inc/story/56749/update-the-libmagic-vcpkg-port-overlay-to-version-5-45)

This PR updates our custom vcpkg port overlay for libmagic to version
5.45. Unlike the last time we attempted this (#4673), this PR does not
replace the port with the upstream autotools-based one, and is not
expected to be a build-breaking change.

---
TYPE: IMPROVEMENT
DESC: Updated libmagic to version 5.45.

[SC-56749](https://app.shortcut.com/tiledb-inc/story/56749/update-the-libmagic-vcpkg-port-overlay-to-version-5-45)

This PR updates our custom vcpkg port overlay for libmagic to version
5.45. Unlike the last time we attempted this (#4673), this PR does not
replace the port with the upstream autotools-based one, and is not
expected to be a build-breaking change.

---
TYPE: IMPROVEMENT
DESC: Updated libmagic to version 5.45.

(cherry picked from commit c44fb49)

Backport #5332 to release-2.26 to fix
conda-forge/tiledb-feedstock#399

---


[SC-56749](https://app.shortcut.com/tiledb-inc/story/56749/update-the-libmagic-vcpkg-port-overlay-to-version-5-45)

This PR updates our custom vcpkg port overlay for libmagic to version
5.45. Unlike the last time we attempted this (#4673), this PR does not
replace the port with the upstream autotools-based one, and is not
expected to be a build-breaking change.

---
TYPE: IMPROVEMENT
DESC: Updated libmagic to version 5.45.

(cherry picked from commit c44fb49)

<long description>

---
TYPE: NO_HISTORY | FEATURE | BUG | IMPROVEMENT | DEPRECATION | C_API |
CPP_API | BREAKING_BEHAVIOR | BREAKING_API | FORMAT
DESC: <short description>

---------

Co-authored-by: Theodore Tsirpanis <[email protected]>