[msbuild] Remove a lot of legacy logic + a few improvements.

[rolfbjarne]

• Remove a lot of legacy build logc.
• Unify the installed files: we now install all files on all platforms (except
  files related to remote windows support). This simplifies the build logic,
  and doesn't increase the nupkg size in any significant way, because these
  are tiny text files.
• Completely merge Xamarin.iOS.Tasks.dll and Xamarin.Mac.Tasks.dll into
  Xamarin.MacDev.Tasks.dll, and remove the two former assemblies. This also
  simplifies a lot of build logic.
• Ship the translations for our task assemblies in .NET (seems like this was
  overlooked in the .NET migration).

[vs-mobiletools-engineering-service2]

✅ [CI Build] Build passed (Build macOS tests) ✅

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build] Tests on macOS M1 - Mac Monterey (12) passed 💻

✅ All tests on macOS M1 - Mac Monterey (12) passed.

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build] Tests on macOS M1 - Mac Ventura (13) passed 💻

✅ All tests on macOS M1 - Mac Ventura (13) passed.

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build] Tests on macOS X64 - Mac Sonoma (14) passed 💻

✅ All tests on macOS X64 - Mac Sonoma (14) passed.

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

✅ [CI Build] Build passed (Build packages) ✅

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build] Windows Integration Tests passed 💻

✅ All Windows Integration Tests passed.

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

🚀 [CI Build] Test results 🚀

Test results

✅ All tests passed on VSTS: test results.

🎉 All 105 tests passed 🎉

Tests counts

✅ cecil: All 1 tests passed. Html Report (VSDrops) Download
✅ dotnettests (iOS): All 1 tests passed. Html Report (VSDrops) Download
✅ dotnettests (MacCatalyst): All 1 tests passed. Html Report (VSDrops) Download
✅ dotnettests (macOS): All 1 tests passed. Html Report (VSDrops) Download
✅ dotnettests (Multiple platforms): All 1 tests passed. Html Report (VSDrops) Download
✅ dotnettests (tvOS): All 1 tests passed. Html Report (VSDrops) Download
✅ framework: All 2 tests passed. Html Report (VSDrops) Download
✅ fsharp: All 4 tests passed. Html Report (VSDrops) Download
✅ generator: All 5 tests passed. Html Report (VSDrops) Download
✅ interdependent-binding-projects: All 4 tests passed. Html Report (VSDrops) Download
✅ introspection: All 4 tests passed. Html Report (VSDrops) Download
✅ linker: All 40 tests passed. Html Report (VSDrops) Download
✅ monotouch (iOS): All 7 tests passed. Html Report (VSDrops) Download
✅ monotouch (MacCatalyst): All 8 tests passed. Html Report (VSDrops) Download
✅ monotouch (macOS): All 9 tests passed. Html Report (VSDrops) Download
✅ monotouch (tvOS): All 9 tests passed. Html Report (VSDrops) Download
✅ msbuild: All 2 tests passed. Html Report (VSDrops) Download
✅ xcframework: All 4 tests passed. Html Report (VSDrops) Download
✅ xtro: All 1 tests passed. Html Report (VSDrops) Download

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

✅ [CI Build] Build passed (Detect API changes) ✅

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]

[vs-mobiletools-engineering-service2]

✅ API diff for current PR / commit

.NET (No breaking changes)

• iOS: vsdrops gist (No breaking changes)
• tvOS: vsdrops gist (No breaking changes)
• MacCatalyst: vsdrops gist (No breaking changes)
• macOS: vsdrops gist (No breaking changes)

✅ API diff vs stable

.NET (No breaking changes)

• iOS: vsdrops gist (No breaking changes)
• tvOS: vsdrops gist (No breaking changes)
• MacCatalyst: vsdrops gist (No breaking changes)
• macOS: vsdrops gist (No breaking changes)

ℹ️ Generator diff

Generator Diff: vsdrops (html) vsdrops (raw diff) gist (raw diff) - Please review changes)

Pipeline on Agent
Hash: 1979db515e9d74e7afd1803c17d025a4b8b47465 [PR build]