fix: Ensure LocationFull validates state data before relaying it to history API

[webJose]

No description provided.

[Copilot]

Pull Request Overview

This PR adds state validation to the LocationFull class to ensure that only conformant state objects are passed to the browser's history API. When non-conformant state is detected, it logs a warning and preserves the previous valid state instead.

• Imports and uses the isConformantState function to validate state objects before they reach the history API
• Updates error handling in navigation cancellation to use event.state instead of the raw state parameter
• Adds comprehensive test coverage for the new validation behavior and improves existing test cleanup

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/lib/core/LocationFull.ts	Adds state validation logic and imports the validation function
src/lib/core/LocationFull.test.ts	Removes unused import, improves test cleanup, and adds tests for state validation

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