feat: implement ADR-297 phase-2 world-model core — HAL, ground-truth, tracking, fusion

The layer that turns the certificate spine into a modality-agnostic perception
substrate. Four crates, all deterministic and green independently (43 tests).

ruview-hal (ADR-317): one abstraction mapping any modality (CSI/802.11bf/BLE/
UWB/mmWave/acoustic/camera/lidar/IMU/custom) to a canonical ontology Observation.
SensorHal trait + two SYNTHETIC/L0 reference adapters; malformed input yields a
degraded UNKNOWN observation, never a panic; synthetic can never alias measured.
8 tests.

ruview-groundtruth (ADR-300): reference sensors as a formal VALIDATION plane
(never an estimator input, enforced by the type boundary); modality-agnostic
ReferenceSeries, deterministic cross-correlation alignment, AgreementReport with
mandatory SessionScope, emitting per-context ruview-evidence records; Measured
requires reference + coverage + reproducer. 15 tests.

ruview-track (ADR-304): privacy-preserving persistent tracks (opaque person ids,
coarse non-reversible features, no civil-identity binding); ambiguous detections
stay tentative rather than misassigned; cross-zone hand-off. 8 tests.

ruview-fusion (ADR-308): multiple HalObservations -> one probabilistic WorldState,
uncertainty-aware (confidence-weighted, not naive averaging); irreconcilable
conflict or insufficient coverage yields UNKNOWN, not a confident average.
9+ tests incl. irreconcilable_conflict_yields_unknown.

Flips ADR-300/304/308/317 to implemented; registers the four crates as workspace
members. SYNTHETIC/L0 throughout; no hardware/MEASURED claims.

Co-Authored-By: claude-flow <ruv@ruv.net>
Claude-Session: https://claude.ai/code/session_015TcKegTS7QqhWPC2L2SzaS

docs/adr/ADR-300-ground-truth-synchronization.md

@@ -1,6 +1,6 @@
 # ADR-300: Ground-truth synchronization — reference sensors as a formal validation plane
 
-- **Status**: Proposed (ADR-297 phase 2)
+- **Status**: Accepted — initial implementation (ADR-297 phase 2)
 - **Date**: 2026-08-11
 - **Deciders**: ruv
 - **Tags**: ground-truth, validation, fusion, evidence, benchmark, honesty, substrate

docs/adr/ADR-304-persistent-identity-tracking.md

@@ -1,6 +1,6 @@
 # ADR-304: Persistent identity & tracking — privacy-preserving probabilistic tracks
 
-- **Status**: Proposed (ADR-297 phase 2)
+- **Status**: Accepted — initial implementation (ADR-297 phase 2)
 - **Date**: 2026-08-11
 - **Deciders**: ruv
 - **Tags**: tracking, identity, privacy, fusion, worldgraph, phase-2

docs/adr/ADR-308-real-sensor-fusion.md

@@ -1,6 +1,6 @@
 # ADR-308: Real sensor fusion — uncertainty-aware, multiple observations → one world state
 
-- **Status**: Proposed (ADR-297 phase 2)
+- **Status**: Accepted — initial implementation (ADR-297 phase 2)
 - **Date**: 2026-08-11
 - **Deciders**: ruv
 - **Tags**: fusion, uncertainty, multimodal, world-state, ontology, phase-2

docs/adr/ADR-317-sensor-hal.md

@@ -1,6 +1,6 @@
 # ADR-317: RuView sensor HAL — abstract all sensing hardware to one Observation type
 
-- **Status**: Proposed (ADR-297 phase 2)
+- **Status**: Accepted — initial implementation (ADR-297 phase 2)
 - **Date**: 2026-08-11
 - **Deciders**: ruv
 - **Tags**: hal, sensor-abstraction, ontology, fusion, adapters, category, phase-2