fix: complete-flow spec flaky test

[dluffy56]

Issue: #1531
Previously PRs: #1597, #1599

Description

Problem

The test complete-flow spec was flaky because it used broad page.locator("tbody") selectors to check table content. When multiple invoice rows were present, assertions were matching the entire table body instead of a specific row, causing unreliable failures.

Additionally, the date picker (React Aria spinbutton) sometimes did not fully commit the year value. In some runs, Dec 1, 2024 was being saved/rendered as Dec 1, 202, which caused the assertion to fail intermittently.

Solution

Changed from broad tbody selectors to row-specific selectors using page.locator("tbody tr").filter({ hasText: "CUSTOM-X" }). This ensures assertions are targeted to the specific invoice row instead of the entire table body.

Also stabilized the fillDatePicker helper by clearing the field first, typing sequentially with delay, blurring the input to trigger commit, and asserting the final value to guarantee the full year is saved.

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Test Results

Tested with --repeat-each=20 --workers=1 - all 20 test runs passed

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Checklist

• I have read the contributing guidelines
• I have watched Gumroad PR review livestreams
• I have performed a self-review and left review comments on my PR
• I have added/updated tests for my changes

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AI Disclosure

Used Claude Opus 4.5 to understand the issue and implement the fix. Code was reviewed and tested manually.