test: stabilize async remote mutation tests

[svelte-triage-bot]

Fixes two pre-existing async e2e flakes exposed by the CI run for #16892.

The form reconnect test previously polled a server-side iterator cleanup counter. The failed traces show that the form response succeeded and the targeted get_count connection restarted, but transport cleanup had not updated the counter within the assertion window. Assert the observable reconnect requests directly instead, including that get_finite_count is not reconnected.

The serial batch tests also retained module-level todo mutations across retries. Reset the todos before asserting the baseline state so reruns are idempotent.

Failed workflow: https://github.com/sveltejs/kit/actions/runs/32541364509

Verification:

• primary test: 100 dev repetitions and 100 build repetitions
• batch mutation sequence: 40 tests
• relevant dev tests with two workers: 120 tests
• relevant build tests: 60 tests
• pnpm -F test-async check
• formatting and diff checks

[pkg-svelte-dev]

Install the latest version of @sveltejs/kit from a425290:

pnpm add https://pkg.svelte.dev/@sveltejs/kit/c/a4252909c77a1117b01a588c653a6919f3fcbca2

Open in pkg.svelte.dev: https://pkg.svelte.dev/repos/kit/pr/16896

Note

This PR is from a fork. A maintainer must approve approve each commit before it can be built and installed.

[changeset-bot]

⚠️ No Changeset found

Latest commit: a425290

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