perf(desktop): optimize legacy camera preview with frame reuse and dr… #6502

Job	Run time
Format (Cargo)	8s
Typecheck	1m 44s
Format (Biome)	10s
Detect Changes	9s
Lint (Biome)	10s
Rust cache (x86_64-pc-windows-msvc, windows-latest)	9m 56s
Rust cache (x86_64-apple-darwin, macos-latest)	4m 40s
Clippy (x86_64-pc-windows-msvc, windows-latest)	4m 22s
Rust cache (aarch64-apple-darwin, macos-latest)	2m 54s
Clippy (aarch64-apple-darwin, macos-latest)	2m 6s
Build Desktop	0s
Verify Tauri plugin versions	0s
	26m 19s

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