[TheCryptoDonkey]

A cold 4K startup can hold the original response plus three useful futures whose aggregate exceeds the fixed 24 MiB reservoir. The observed catalogue combination requires 27,195,621 bytes; a conservative audit of this recording tops out at 30,602,204 bytes. Retiring the original response would break ownership of its pending HLS callback.

Add explicit startupBufferMaxBytes, default 24 MiB and bounded to 32 MiB. A non-default allowance requires startup buffering and must be reserved against the host's shared budget before HTTP. Independently cap cached/in-flight future bytes at 24 MiB so release preserves the steady cache limit. Per-object limits, four-object startup residency, serial loading, authority, recovery headroom and original deadline stay unchanged. This is an encoded reservoir allowance, not total browser memory.

Validation: actual-size regression RED before implementation and GREEN after it; full swarm672/672, warm suite135/135, six focused cases, syntax 202 modules and documentation 30 authored files/450 links pass. Regressions include invalid options, shared-budget refusal before HTTP, independent future cap, cancellation/deadline and original response/stats/context ownership. Independent review found no blockers. Playback and physical-device acceptance remain separate; the preceding source-only late join still failed its deadline.

#47 is merged; the website will explicitly opt into 32 MiB for its full-recording startup within its existing 64 MiB shared held budget.