Implementation plan: wave-based decomposition; waves 1-2 decomposed (11 tasks)

docs/plans/implementation.md records the wave structure (core ->
substrate fork || pg engine -> sqlite engine -> contract suite ->
release), the decided points (contract-suite layout = option (a),
engine-tests vs equivalence-suite split, no CI, mem-engine/fuzzing
deferrals surfaced), and the review-gate rhythm.

Wave 1 (foundations): workspace scaffold, core errors/validation,
value types, trait surface, contract-suite scaffold (+ADR-022),
review gate.
Wave 2 (substrate fork): fork scaffold/provenance, connection+watcher
port, queue-op re-derivation on contract v1, provenance/floor close,
review gate.

tasks/review-wave-1.md

@@ -0,0 +1,68 @@
+---
+id: review-wave-1
+name: Review gate — wave 1 (core contract surface)
+status: pending
+depends_on: [core-trait-surface, contract-suite-scaffold]
+scope: narrow
+risk: low
+impact: project
+level: review
+tags: [wave-1, review]
+---
+
+## Description
+
+Review the wave-1 output before wave 2/3/4 work builds on it. The core
+trait surface is versioned contract surface from the first release
+(ADR-017) — a shape error found here is cheap; found in wave 5 it is a
+migration. This review is line-by-line against the pinned ADR text,
+not a general code review.
+
+Check:
+
+- **Trait surface vs. ADR text** — every method set and signature in
+  `core-trait-surface` against ADR-008 §1–§3/§8, ADR-014, ADR-019 §1–§5,
+  ADR-021: exact names, exact field types, the one-shot/repeatable
+  split (`heartbeat(&self)` vs `self: Box<Self>` ops), the
+  `recv_timeout`/no-`recv_timeout` asymmetry between the two receiver
+  traits, `with_tx`'s pinned signature.
+- **Value types vs. ADR text** — `Job`'s full field list (including
+  `claimed_at`, ADR-021 §2), `StreamEvent`'s shape (ADR-015 §3), opts
+  structs' types and defaults (ADR-010 §3, ADR-020), the
+  `#[non_exhaustive]` split (read types yes, opts structs no —
+  ADR-017 §3).
+- **Error taxonomy** — exactly six variants, no extras; `Database`
+  opaque with source chain; the pinning rule respected.
+- **Validation** — both name classes correct (shared-namespace vs
+  consumer-local; ADR-008 §4 third-round annotation).
+- **Family standards** — no panics, no `unwrap()`/`expect()` outside
+  tests, no comments in code (doc comments on public API fine),
+  module-per-file, re-exports from `lib.rs`.
+- **Lean core** — no engine machinery, no resolution arithmetic, no
+  SQL-shaped anything in core (ADR-012 §2's boundary).
+- **Suite scaffold** — ADR-022 exists and is coherent with ADR-017;
+  exemplar property green; stamp convention usable.
+- **Gates** — `cargo test` (workspace), `cargo clippy --all-targets --
+  -D warnings`, `cargo fmt --check` all green.
+
+## Acceptance Criteria
+
+- [ ] Every divergence from pinned ADR text found and fixed (or an ADR
+      amendment proposed if the text itself is wrong)
+- [ ] All gates green
+- [ ] Findings recorded (task Summary or review notes)
+
+## References
+
+- docs/architecture/decisions/008-contract-v1-pinning.md
+- docs/architecture/decisions/019-mechanism-handle-surfaces.md
+- docs/architecture/decisions/021-tx-reads-and-value-shape-fixes.md
+- docs/plans/implementation.md (Review gates)
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion