feat(slice-4): v0.0.49 — core2 yanked unblock + sc-service WIP (crates.io API gap found)

Slice 4 Ship 2 parcial. RESUELVE el blocker real que difirió sc-service 3
sesiones (core2 yanked), pero DESCUBRE un segundo bloqueo arquitectural que
requiere decisión de David. Build verde, 213 tests, sin regresiones.

=== RESUELTO: core2 yanked (el muro de 3 sesiones) ===
sc-network-types 0.16 → cid ^0.9 (0.9.0 yanked) → core2 ^0.4 (0.4.0 yanked,
las no-yanked son 0.3.x que no satisfacen ^0.4). Cargo no auto-selecciona
versiones yanked → resolución fallaba. Era exactamente lo documentado en
chain_spec.rs Slice 3 que difirió sc-service.
Fix: vendorizado el .crate publicado de core2 0.4.0 (yanked pero descargable)
en vendor/core2-0.4.0/ + [patch.crates-io] core2 = { path = ... }. Una path
source es seleccionable independiente del estado yanked. El git source
(technocreatives/core2 master) resultó ser workspace ≤0.3.x, no servía.

=== DESCUBIERTO: crates.io consensus crates ≠ git tag API ===
Las crates sc-/sp- consensus PUBLICADAS (sc-consensus-aura 0.52.0 +
sp-consensus-aura 0.45.0) tienen API DISTINTA al git tag polkadot-stable2509-3
bajo el MISMO número de versión:
- git tag: sc_consensus_aura::standalone::slot_duration_at +
  sp_consensus_aura::inherents::InherentDataProvider::from_timestamp_and_slot_duration
- crates.io: slot_duration_at en root + NO existe slot InherentDataProvider
  (Slot no implementa el trait; Slot::from_timestamp toma 1 arg)
polkadot-sdk reusa números de versión con cambios git no publicados.

Construir un node service real requiere migrar TODO el stack sc-/sp- consensus
a git sources del tag — la misma cirugía duplicate-crate que golpeó pallet-revive
(Ship 2 v0.0.39). Decisión arquitectural para David.

Cambios:
- Cargo.toml: [patch.crates-io] core2 path vendor + sp-timestamp 39 + sp-blockchain 41
- vendor/core2-0.4.0/: crate vendorizado (yanked artifact original)
- node Cargo.toml: 13 sc-* + sp- consensus deps + jsonrpsee/rpc + core2 unblock dep
- node src/service.rs + rpc.rs: WIP escritos (verbatim stable2509-3 + 2 fixes API
  crates.io), NO mod-declarados (preservados para siguiente fase)
- node src/main.rs: finding documentado, mods service/rpc neutralizados

Verificación:
- cargo check -p origin-chain-node: EXIT 0 (deps resuelven vía core2, mods off)
- cargo test --workspace: 213 verde, 0 fail, sin regresiones
- core2 0.4.0 + cid 0.9.0 ahora en Cargo.lock (vía path patch)

Próximo: decisión David — (A) migrar sc-/sp- consensus a git sources tag
stable2509-3 (real node, riesgo duplicate-crate) vs (B) mantener publicadas
(node service diferido a futura generación Substrate). Ver SLICE_4 plan §10.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

vendor/core2-0.4.0/LICENSE-MIT

@@ -0,0 +1,19 @@
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