Refresh hero preview for reel_text 0.4.2

[KickNext]

Summary

Refresh the README hero animation so it reflects the current reel_text 0.4.2 package instead of showing the original 0.1.3 version cue.

The previous WebP was captured when the package was first released. Because the hero loads the version from pubspec.yaml, the recorded artifact kept displaying that stale value even though the live example had moved on. Its captured canvas was also transparent and relied on the WebP animation background hint, which some viewers ignore and render as black.

The replacement re-records the same full hero choreography from the current example at 1280x720 and 60 fps. All 1,542 frames now contain an opaque #f8f9fa background, so the preview remains light in viewers that do not honor the container background hint.

Validation

• Parsed 1,542 WebP animation frames with a total duration of 25.7 seconds (60 fps).
• Confirmed the canvas is 1280x720 and the animation loops indefinitely.
• Sampled the first, version, and final frames and verified their alpha channel is fully opaque with #f8f9fa corner pixels.
• Visually confirmed the recorded version cue displays v0.4.2.