fix: Stopwatch implementation on pre-release version 10.1.0-rc1

[vbreuss]

This PR completes the release workflow for core library version 10.1.0-rc1 by updating package versions and restoring the build pipeline to build all projects (both core and main).

Key Changes:

• Bumps core package versions from 10.0.0 to 10.1.0-rc1 in Directory.Packages.props
• Resets BuildScope from CoreOnly to Default to enable building all projects again
• Simplifies TestHelpers project references by removing unused Testably.Abstractions dependency

[Copilot]

Pull request overview

This PR completes the release workflow for core library version 10.1.0-rc1 by updating package versions and restoring the build pipeline to build all projects (both core and main).

Changes:

• Bumps core package versions from 10.0.0 to 10.1.0-rc1 in Directory.Packages.props
• Resets BuildScope from CoreOnly to Default to enable building all projects again
• Simplifies TestHelpers project references by removing unused Testably.Abstractions dependency

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
Directory.Packages.props	Updates Testably.Abstractions.Interface and Testably.Abstractions package versions to 10.1.0-rc1
Pipeline/Build.cs	Resets BuildScope to Default, re-enabling full build pipeline after core version bump
Tests/Helpers/Testably.Abstractions.TestHelpers/Testably.Abstractions.TestHelpers.csproj	Removes unused Testably.Abstractions reference and changes Interface reference pattern

[github-actions]

Test Results

     52 files  +     51       52 suites  +51   36m 42s ⏱️ + 36m 42s
 64 490 tests + 64 477   60 875 ✅ + 60 863   3 615 💤 + 3 614  0 ❌ ±0 
133 814 runs  +133 801  119 270 ✅ +119 258  14 544 💤 +14 543  0 ❌ ±0 

Results for commit 34a8129. ± Comparison against base commit bcc0254.

♻️ This comment has been updated with latest results.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[github-actions]

This is addressed in release v5.3.0.