feat: Add ignoreForFallback property to Route

[webJose]

This also removes the when property.

Fixes #20.

[Copilot]

Pull Request Overview

This PR adds a new ignoreForFallback property to Route components while removing the when property. The purpose is to allow routes to be ignored when determining whether fallback content should be displayed, providing more granular control over route matching behavior for fallback scenarios.

• Replaces the when predicate function with a simpler boolean ignoreForFallback property
• Updates route matching logic to consider the ignoreForFallback flag when calculating noMatches
• Adds comprehensive test coverage for the new fallback behavior

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/lib/types.ts	Removes WhenPredicate type and updates CoreRouteInfo to replace when with ignoreForFallback
src/lib/core/RouterEngine.svelte.ts	Updates route pattern parsing and matching logic to handle ignoreForFallback property
src/lib/core/RouterEngine.svelte.test.ts	Adds test cases for noMatches behavior with ignoreForFallback routes
src/lib/Route/Route.svelte	Updates Route component to use ignoreForFallback instead of when property
src/lib/Route/README.md	Updates documentation to reflect the new ignoreForFallback property

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