feat(RouterEngine)!: Rename noMatches to fallback and make resolvedHash public

[webJose]

BREAKING CHANGE

[Copilot]

Pull request overview

This PR renames the noMatches property to fallback across the codebase and changes the resolvedHash property from private to public in the RouterEngine class. These are breaking changes that improve API clarity by using more intuitive naming.

Key changes:

• Renamed noMatches to fallback throughout the codebase (property, variables, documentation)
• Changed #resolvedHash from private to public resolvedHash property
• Updated all references in types, tests, and documentation

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/lib/types.ts	Updated WhenPredicate type signature parameter from noMatches to fallback
src/lib/kernel/RouterEngine.svelte.ts	Changed #resolvedHash to public resolvedHash and renamed noMatches property/variables to fallback
src/lib/kernel/RouterEngine.svelte.test.ts	Updated test suite to use fallback instead of noMatches
src/lib/Fallback/README.md	Updated documentation to reference fallback instead of noMatches
src/lib/Fallback/Fallback.svelte	Updated component logic to use router.fallback instead of router.noMatches
AGENTS.md	Updated agent documentation to reflect the fallback terminology

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