fix: add support for trailing slashes in typed routes

[yuki0418]

Fixes #14047

Add pathnames with a trailing slash when generating typed routes.

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🦋 Changeset detected

Latest commit: 0096db2

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@sveltejs/kit	Patch

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[Copilot]

Pull Request Overview

This PR adds support for trailing slashes in typed routes to fix issue #14047. The change ensures that both versions of pathnames (with and without trailing slashes) are included in the generated type definitions.

Key changes:

• Modified pathname generation logic to include trailing slash variants for all non-root routes
• Added test cases to verify trailing slash support in typed routes

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
packages/kit/src/core/sync/write_types/index.js	Core logic update to generate both trailing and non-trailing slash pathname types
packages/kit/src/core/sync/write_types/test/app-types/+page.ts	Test cases added to verify trailing slash pathname support
.changeset/curvy-bugs-build.md	Changeset documentation for the patch fix

[yuki0418]

I want to add trailing slash only when export const trailingSlash = 'always'; is in a file.
But I could find a way to check it.

[yuki0418]

Also I just add a trailing slash to type Pathname because user would not enter Router Id in href.
Sorry if I'm wrong.