[kevmo314]

Replace the custom network image loader and disk-only placeholder provider with CachedNetworkImageProvider throughout chat, emote input/autocomplete/picker, badges, avatars, and previews. Cached images display immediately while stale entries refresh through the library. Existing dimensions, fades, transparent placeholders, and chat emote text fallbacks are preserved; animated image bytes are not resized or re-encoded.

Replaces #1715. The dependency is installed from kevmo314/flutter_cached_network_image at commit 4c24ee00b4fe69144a37e2cd4067eb74eabf1348, pinned in both pubspec.yaml and pubspec.lock. That commit fixes an undisposed queued animation frame in published 4.0.5. The fix is submitted upstream as Baseflow/flutter_cached_network_image#1065, with five regression tests and all 56 upstream tests passing. Switch back to a hosted dependency once the fix is released.

Validation

• flutter pub get: resolves the actual Git dependency from the pinned fork commit, with no local dependency overrides.
• flutter test --no-pub: all 493 tests pass, including the image leak checker.
• flutter analyze --no-pub: passes.
• dart format --output=none --set-exit-if-changed .: passes.
• Five integration tests verify rendered GIF/WebP animation loops in chat and the picker, animation after clearing Flutter's memory cache and reopening persisted disk-cache metadata offline, and the emote text fallback when loading fails. The image leak checker remains enabled.

The image tests use Flutter's real decoder and real temporary disk files with controlled HTTP responses. Android/iOS device smoke tests were not run locally; native builds are covered by PR CI.

History

The available non-shallow git history and GitHub issue search contain no earlier cached_network_image usage. The custom loader was introduced by #439 in May 2022, replacing flutter_image/NetworkImageWithRetry to address #403's network-failure, retry, caching, and placeholder requirements. Those records do not identify a prior format-support problem; GIF and animated WebP playback are explicitly tested here.