PulseLoop 2.8.0 (43)

Test build — rc3, follow-up to rc2. Prerelease, so the in-app updater won't offer it to anyone else. Everything confirmed working in rc1 and rc2 is unchanged.

Built from @Albabit's five SpO₂ captures and the ring-history read-back on #59, plus a review pass over the PR.

What changed

• SpO₂ settles on the last plausible sample, because that is what the ring itself logs. Read back against the ring's own history, the last sample matched five runs out of five; the median matched four. The vendor app agrees: it shows each frame and re-reads history on 04 0e. Plausibility band 70–100, as the vendor uses.
• The SpO₂ window is 75 s on this ring family. Every capture put 04 0e at t+63.1 s, three seconds after the old 60 s window gave up and fell back to settling on its own.
• A spot reading the ring logs itself is no longer doubled. Our settled reading is stored, and when the next sync brings in the ring's own copy of that same measurement (same kind, within 90 s), ours yields to it. That is the 79/82 pair from rc1.
• Intermediate samples can no longer slip past the one-reading rule while the storage side is catching up on a busy sync.
• Blood pressure and HRV no longer treat the ring's success verdict as a failure (those legs read no value from 04 0e; the ring re-supplies it from history).
• Diagnostics masking keeps the routing header for the R10M family too, not only TK5.

What would help

• @Albabit — a few spot SpO₂ measurements: does the number now match what the Da Rings-side history stores for that run (your Python read-back is the ground truth here), and does the leg end on the ring's 04 0e rather than the window? Then a history sync afterwards: the reading should stay one row, and it should be the ring's.
• @scufitarosie — nothing new is expected to change on the R100, but an install and a sync to confirm temperature, SpO₂ and the R100 card all still behave as on rc1 would rule out a regression before this merges.