fill_in races with phx-change: clear triggers patch before set_value

[pinetops]

Problem

fill_in calls clear() then set_value(). Both trigger phx-change on the form:

1. clear() → empties input → phx-change fires with email: ""
2. set_value() → types characters → phx-change fires with email: "user@test.com"

with_patch_await wraps fill_in and resolves after the FIRST patch (from clear). The test continues, click("Submit") fires before the server has processed set_value's change event. The server state still has an empty email.

Evidence

Screenshot shows the sign-in form with an empty email field after fill_in + click sequence. Intermittent under concurrent load.

Fix options

1. fill_in should await patch after set_value, not after clear — move with_patch_await to wrap only set_value, or await twice
2. clear should not trigger phx-change — use JS to clear without dispatching input/change events
3. Debounce-aware fill_in — after typing, wait for the debounce period + patch before returning