[Foundation] Ensure NSUrlSessionHandler's session is cleaned up on dispose. Fixes #24376.

[rolfbjarne]

Fixes #24376

Doc references:

• https://developer.apple.com/documentation/foundation/urlsession/invalidateandcancel()
• https://developer.apple.com/documentation/foundation/urlsession/finishtasksandinvalidate()

Continuation of #24377 by @dotMorten.

[Copilot]

Pull request overview

This PR fixes issue #24376 by ensuring that NSUrlSessionHandler properly invalidates its underlying NSUrlSession when disposed. The fix adds a call to InvalidateAndCancel() in the Dispose method, which is critical for background sessions that need to be properly cleaned up to allow the same session identifier to be reused.

• Adds session.InvalidateAndCancel() call in the Dispose method
• Includes a comprehensive test verifying background session handlers can be disposed and recreated with the same identifier

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
src/Foundation/NSUrlSessionHandler.cs	Adds InvalidateAndCancel() call in the Dispose method to properly clean up the session
tests/monotouch-test/System.Net.Http/NSUrlSessionHandlerTest.cs	New test file with test case verifying background session cleanup and recreation works correctly

[vs-mobiletools-engineering-service2]

✅ [CI Build #60a35a0] Build passed (Build packages) ✅

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

✅ [PR Build #60a35a0] Build passed (Detect API changes) ✅

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

✅ API diff for current PR / commit

NET (empty diffs)

• 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 (empty diffs)

• 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: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

✅ [CI Build #60a35a0] Build passed (Build macOS tests) ✅

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build #60a35a0] Tests on macOS X64 - Mac Sonoma (14) passed 💻

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

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build #60a35a0] Tests on macOS M1 - Mac Monterey (12) passed 💻

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

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build #60a35a0] Tests on macOS arm64 - Mac Tahoe (26) passed 💻

✅ All tests on macOS arm64 - Mac Tahoe (26) passed.

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build #60a35a0] Tests on macOS arm64 - Mac Sequoia (15) passed 💻

✅ All tests on macOS arm64 - Mac Sequoia (15) passed.

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

💻 [CI Build #60a35a0] Tests on macOS M1 - Mac Ventura (13) passed 💻

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

Pipeline on Agent
Hash: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]

[vs-mobiletools-engineering-service2]

🚀 [CI Build #60a35a0] Test results 🚀

Test results

✅ All tests passed on VSTS: test results.

🎉 All 121 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 6 tests passed. [attempt 2] Html Report (VSDrops) Download
✅ linker: All 44 tests passed. Html Report (VSDrops) Download
✅ monotouch (iOS): All 9 tests passed. Html Report (VSDrops) Download
✅ monotouch (MacCatalyst): All 11 tests passed. Html Report (VSDrops) Download
✅ monotouch (macOS): All 9 tests passed. Html Report (VSDrops) Download
✅ monotouch (tvOS): All 11 tests passed. [attempt 2] Html Report (VSDrops) Download
✅ msbuild: All 2 tests passed. Html Report (VSDrops) Download
✅ windows: All 3 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: 60a35a08a7f22d9bbde2622920a8dba7ead25126 [PR build]