fix: enable ts check in .svelte and some hidden problems

[exoticknight]

No description provided.

[Copilot]

Pull Request Overview

This PR enables TypeScript checking for .svelte files and addresses several hidden issues by refining type definitions and state handling within the codebase. Key changes include:

• Removal of the examples directory from the main tsconfig.svelte.json, relying on a dedicated config file for examples.
• Updating error and abort controller state initialization in Chat from null to undefined.
• Adjustments to snippet parameter types and minor dependency updates in package configurations.

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tsconfig.svelte.json	Removed the examples folder from the include array to delegate type-checking to a separate config.
packages/svelte/src/chat.svelte.ts	Modified error and abort controller state assignments to use undefined instead of null.
packages/shared/src/types/ui.ts	Reformatted type definition for UIMessagePart without functional changes.
packages/shared/src/types/stream-text.ts	Reformatted type definition for StreamTextDataChunk.
package.json	Updated dependency versions to their latest patches.
examples/svelte/tsconfig.json	Added a dedicated tsconfig for Svelte examples.
examples/svelte/src/message-bubble.svelte	Enhanced snippet parameter type annotations and implemented optional chaining.
examples/svelte/src/app.svelte	Updated attachment and tool typing, and ensured consistency in error state usage.
examples/svelte/package.json	Updated Svelte version.
examples/react/src/ui-message-part.tsx	Adjusted template rendering to directly access properties.
.vscode/settings.json	Enabled the Svelte TypeScript plugin.

Comments suppressed due to low confidence (3)

tsconfig.svelte.json:14

• Removal of 'examples/svelte/src' from the tsconfig include array may affect type-checking; confirm that the separate config for examples adequately covers the necessary files.

   -    "examples/svelte/src",

packages/svelte/src/chat.svelte.ts:28

• Changing the initial value of #error from null to undefined might affect consumers expecting a nullable error; ensure that all related type checks and usages are updated accordingly.

#error = $state<Error>()

packages/svelte/src/chat.svelte.ts:49

• Switching from null to undefined for #abortController requires consistent handling across the code; verify that all checks against this property use undefined instead of null.

#abortController: AbortController | undefined