SeekQuote Web v0.1.8

TikTok / iPhone movie export hardening
- Keeps the movie renderer and 30fps H.264-first MediaRecorder pipeline matched to the known-working SeekQuote 2.0 v2.22.0 extension.
- On iPhone/iPad WebKit, uses manual canvas frame requests when supported so every rendered frame is explicitly delivered to the recorder instead of allowing static frames to be coalesced.
- Requests a 1-second keyframe interval on browsers that support the MediaRecorder option, with automatic fallback to the extension's original recorder settings.
- Leaves the existing Save Video to Photos web workflow intact.
