docs(spf): mark non-zero-PTS relocation implemented for VOD

Update presentation-timeline-model + non-zero-pts-support docs: status
draft→implemented, mechanism resolved (timestampOffset relocation, VOD
scope), and point at the shared-min origin + establishStartMediaTime /
relocation-pipelines surface.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

internal/design/spf/features/non-zero-pts-support.md

@@ -1,5 +1,5 @@
 ---
-status: draft
+status: implemented
 date: 2026-05-20
 definition: technical
 ---
@@ -15,14 +15,17 @@ The cluster B foundation; consumed by every cluster A feature
 ([live-stream-support](./live-stream-support.md),
 [dvr-event-stream-support](./dvr-event-stream-support.md),
 [ll-hls-support](./ll-hls-support.md)) for correct `currentTime` /
-`seekable` semantics. **Implementation mechanism is an open
-architectural question** — two viable approaches with different
-trade-offs (see Open questions): apply the offset to the SourceBuffer
-via `timestampOffset` (browser handles the translation; A/V sync risk
-from per-buffer offset divergence) vs simulate the offset via adapter
-+ math in behaviors/compositions (buffer holds original PTS;
-translation happens at every consumer boundary; no A/V drift risk
-but bigger translation surface).
+`seekable` semantics. **Mechanism: resolved** — the `timestampOffset`
+relocation approach (offset applied per `SourceBuffer` so buffer, model,
+and `currentTime` all stay 0-based, adapter untouched) is implemented for
+VOD on `feat/spf-non-zero-pts-relocation`; the A/V-sync risk from
+per-buffer offset divergence is handled by relocating every track by one
+shared `min` origin, which preserves real skew. See
+[presentation-timeline-model.md](../presentation-timeline-model.md) for the
+coordinate model + architecture and
+[../../decisions/mse-timestamp-offset.md](../../decisions/mse-timestamp-offset.md)
+for the mechanism decision. (The alternative — simulated translation in the
+adapter — was the parked approach on `feat/spf-non-zero-pts`.)
 
 A **Media-src feature** in the framing from
 [clusters.md § Feature classification axes](./clusters.md#feature-classification-axes):
@@ -37,11 +40,14 @@ distinct motivations.
 
 ## Status
 
-- **Composition:** not implemented in `createSimpleHlsEngine`. No
-  PTS-handling code in `packages/spf/src/` (no `timestampOffset`,
-  `initPTS`, or `EXT-X-DISCONTINUITY` references). Engine implicitly
-  assumes zero-based PTS — works for typical Mux Video VOD sources
-  (transcoded with PTS rebased to zero) but breaks for live + clips.
+- **Composition:** implemented for VOD in `createSimpleHlsEngine` (and
+  `createHlsAudioOnlyEngine`) on `feat/spf-non-zero-pts-relocation`. The
+  `establishStartMediaTime` reactor (`playback/behaviors/`) + the
+  `relocation-pipelines` primitive (`playback/primitives/`) discover each
+  track's decode-time origin (`tfdt`/`mdhd`, matched by `track_id`) and
+  relocate via `SourceBuffer.timestampOffset = −startMediaTime`. Live is
+  parked on `feat/spf-non-zero-pts`; mid-stream discontinuity remains the
+  sister `[discontinuity-handling]` feature's scope.
 - **Definition depth:** technical — scope and SPF touchpoints
   articulated against MSE `timestampOffset` semantics + HLS spec;
   implementation specifics open. Source material: [SPF Epics Working

internal/design/spf/presentation-timeline-model.md

@@ -1,5 +1,5 @@
 ---
-status: draft
+status: implemented
 date: 2026-07-07
 ---
 
@@ -10,8 +10,9 @@ timelines a streaming presentation lives on — **media**, **presentation**, and
 **wall-clock** — and the architecture for **non-zero-PTS `timestampOffset`
 relocation** built on it.
 
-This is a design-in-progress for the `timestampOffset`-relocation approach to
-non-zero-PTS (spike branch `spike/spf-non-zero-pts-timestamp-offset`). It is the
+This is the design for the `timestampOffset`-relocation approach to non-zero-PTS,
+implemented for **VOD** on branch `feat/spf-non-zero-pts-relocation` (live is parked on
+`feat/spf-non-zero-pts`). It is the
 "how it's modeled and where it lives" companion to the mechanism decision in
 [../../decisions/mse-timestamp-offset.md](../../decisions/mse-timestamp-offset.md)
 and the feature framing in