verify-changes

How to test and verify work in the dev-3.0 repo — which vitest config covers what, how to write a test that fits the house style, mocking Electrobun RPC and i18n providers, what coverage is actually expected, and the browser QA hand-off. Use when writing or fixing tests, deciding what a change needs covered, hitting a failing or flaky suite, or preparing a change for review. Triggers — "write tests for this", "which config runs this", "how do I mock the RPC", "is this covered enough", "the suite is failing".