Add browser mode for running tests in browsers

[Copilot]

• Explore the repository structure and understand the testing framework architecture
• Review how @cross/runtime detects browser environment (supports Runtime.Browser)
• Verify existing tests pass on Deno
• Design browser shim that works without external dependencies
• Implement browser shim (shims/browser.ts) following existing patterns
• Update mod.ts to conditionally load browser shim when Runtime.Browser is detected
• Export browser-specific helper functions (getTestResults, printTestSummary)
• Add browser-specific documentation to README
• Run code review and address feedback
• Run codeql security scan (no issues found)
• Update README example to use JSR import via esm.sh CDN
• Bump version to 0.0.15 for browser support release

Original prompt

Explore if its possible to add a browser mode, to run tests using the exact same framework in browsers. Explore how it could be made practically without added dependencies or too much code overhead. Use jsr:@cross/runtime if a dependency for determinating runtime is needed.

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[Hexagon]

@copilot In the example, use the latest version from jsr in the readme/docs example

[Copilot]

@copilot In the example, use the latest version from jsr in the readme/docs example

Updated the example to import from https://esm.sh/jsr/@cross/test which provides direct browser access to the latest JSR version without requiring bundling. (0ef194d)

[Hexagon]

@copilot bump relevant version if not already bumped since last release

[Copilot]

@copilot bump relevant version if not already bumped since last release

Bumped version from 0.0.14 to 0.0.15 for the browser support release. (023e518)