GH-51007: [C++] Make uriparser an external dependency

[imtherealnaska]

Rationale for this change

Updating the uriparser version so as to include security fixes. Rather than refreshing vendored copy , this makes uriparser and external dependency.

What changes are included in this PR?

AI generated, because there are too many changes and might miss some

• uriparser added to ARROW_THIRDPARTY_DEPENDENCIES, with a
  build_uriparser() ExternalProject pinned to 1.0.2 (docs, tests, tools
  and wchar_t support disabled; static; URI_STATIC_BUILD on the
  interface; registered in ARROW_BUNDLED_STATIC_LIBS).
• REQUIRED_VERSION "1.0.2", so every build gets a uriparser carrying all
  fixes through 1.0.2.
• New cmake_modules/FinduriparserAlt.cmake. Upstream ships a CMake package
  config, but Debian/Ubuntu's liburiparser-dev installs only
  liburiparser.pc, so the module tries find_package(CONFIG) first, then
  pkg-config, then a plain library search.
• ARROW_STATIC_INSTALL_INTERFACE_LIBS gains uriparser::uriparser for
  SYSTEM builds, so static consumers link correctly.
• meson: new subprojects/uriparser.wrap (method = cmake, same tarball
  and checksum as the CMake pin) plus a cmake.subproject fallback, since
  meson has no BUNDLED equivalent.
• cpp/src/arrow/vendored/uriparser/ (28 files) and its LICENSE.txt
  section removed; util/uri.cc now includes <uriparser/Uri.h>.
• Packaging: 6 dockerfiles, conda, Brewfile, both vcpkg manifests, MSYS2
  PKGBUILD and msys2_setup.sh, r_windows_build.sh, the
  -Duriparser_SOURCE passthrough in cpp_build.sh, and the dependency
  list in building.rst.

NOTICE : Having 1.0.2 as floor means ,nearly every distro has to build it from source until they catch up.

Are these changes tested?

All existing tests pass.

Verified on Ubuntu 22.04:

• With 0.9.6 (Distro bundled)present, it finds that the version is not suitable and falls back to building 1.0.2
• Explicit -Duriparser_SOURCE=SYSTEM with 0.9.6 fails .
• Also builds and passes 13/13 on macOS against Homebrew

Are there any user-facing changes?

Now Arrow requires uriparser or builds it . No user facing changes as such because no API changes .

This PR contains a "Critical Fix". It has security fixes that has gone in uriparser.

AI Usage:

• Used for testing <-> building loop.

• GitHub Issue: [C++] Bump vendored uriparser #51007