fix(davinci-client): remove try/catch from update dispatch — errors are now state

We updated two leftover tests that still asserted toThrow for behaviours the PR intentionally converted to error-state writes, and removed the PollingCollector type guard from the reducer that was blocking updater(status) from setting input.value. Without these fixes the e2e polling tests fail because the status string ('timedOut', 'expired') never reaches the SingleValueAutoCollector branch, so next() submits a stale value and the mock API never returns the expected error node.