Add Windows and macOS to build matrix in GitHub Actions run, fix cross-platform issues

[addwes7]

What is the purpose of this PR

Add Windows and macOS to the CI build matrix. Currently the workflow only runs on Ubuntu.

Expected results

Build and tests pass on all three operating systems (Ubuntu, Windows, macOS).

Actual results

Running the workflow on Windows and macOS without fixes produces the following errors:

• Windows: The debug step uses pwd && ls -l. On Windows, ls maps to PowerShell's Get-ChildItem, and -l is interpreted as -LiteralPath, which requires an argument.

• macOS: FontTest.testFontStyleOfStyledFont loads Courier.ttc and expects an OS/2 TrueType table. On macOS, the bundled Courier font does not include that table. This is a platform-specific font difference, not a code defect.

Description of fix

1. Added OS build matrix (ubuntu-latest, windows-latest, macos-latest).
2. Added shell: bash to the debug step so it runs correctly on Windows.
3. Added Assumptions.assumeFalse to skip testFontStyleOfStyledFont on macOS where the required font table is unavailable. An alternative approach would be to comment out or remove the FontFactory.registerDirectories() call.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

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

See analysis details on SonarQube Cloud

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

🟢 Metrics 0 duplication

Metric	Results
Duplication	0

View in Codacy

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