Port the reader screen's chrome to a Robolectric JVM Compose test (umbrella
ReaderScreenJvmTest drives the real ReaderViewModel over a mocked
MailRepository/SettingsRepository via the v2 createComposeRule() — no emulator —
covering the top bar, star/delete/reply/reply-all/forward actions, the
attachment accordion + downloaded indicator, the attachment download-failure
snackbar, and the loading/plain-text/empty/error/remote-images-banner branches.
WebView caveat: the HTML body renders through HtmlBody, a hardened WebView that
Robolectric can only present as a non-rendering shadow, so the banner branch is
driven via an HTML message with a blank body (no HtmlBody call) and no
WebView-rendered HTML is asserted. HtmlBody.kt stays in scope, covered by its
existing HtmlBodyTest/InlineImageResolverTest. The instrumented ReaderScreenTest
stays as the on-device E2E. ReaderScreenKt lands at 94.3% line coverage; the
bundle rises to 82.7%, above the unchanged 0.79 floor.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>