chore: monorepo inicial con arje + minga + yahweh absorbidos

Workspace en 4 ejes (core/modules/apps/shared):

- core/: 24 crates de arje (Init systemd-compatible: ente-card, ente-zero,
  ente-kernel, ente-bus, ente-cas, ente-soma, ente-wasm, ente-snapshot,
  ente-brain, ente-echo, ente-policy-provider, + 12 crates *-compat)
- modules/semantic_dht/: 5 crates de minga (minga-core con AST/CAS/MST,
  minga-p2p con libp2p Kad, minga-store, minga-vfs, minga-cli)
- modules/ui_engine/: 11 crates de yahweh (libs/{core,theme,bus,providers},
  widgets/{tree,splitter,tabs,tiled,container_core,text_input})
- apps/: 5 crates de yahweh (file_explorer, database_explorer, text_viewer,
  image_viewer, yahweh-shell)
- shared_wit/protocol.wit: handshake/lifecycle inicial

Cargo.toml unificado: thiserror bumped a 2 (transparente para arje), tokio
"full", paths intra-workspace de yahweh redirigidos a su nueva ubicación.

cargo check --workspace: 0 errores, 17 warnings (dead code preexistente).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/core/ente-brain/src/lib.rs

@@ -0,0 +1,38 @@
+//! ente-brain: motor de reglas determinista + observador estadístico.
+//!
+//! Tres capas:
+//!   1. `rules`       — tipos de regla (Triplet: Subject + Event + Action)
+//!   2. `engine`      — RuleEngine con HashMap<EventKindDiscriminant, Vec<Arc<Rule>>>
+//!                      para dispatch O(1)
+//!   3. `dispatch`    — ejecutor async de Actions (vía tokio)
+//!   4. `observer`    — sliding window + marginales + co-ocurrencias
+//!                    + Shannon entropy + información mutua
+//!   5. `crystallize` — detección de patrones estadísticamente significativos
+//!                      y materialización en `Rule` ejecutables
+//!   6. `introspect`  — Unix socket bincode API para tools externos
+//!
+//! Diseño de inmutabilidad:
+//!   - Rules son `Arc<Rule>` — clonar es zero-copy (refcount bump).
+//!   - El motor expone sólo lecturas; mutaciones pasan por `insert/remove`.
+//!   - Observer mantiene contadores incrementales — sin recomputación.
+
+pub mod audit;
+pub mod autopromote;
+pub mod crystallize;
+pub mod dispatch;
+pub mod engine;
+pub mod introspect;
+pub mod loader;
+pub mod metrics;
+pub mod observer;
+pub mod rules;
+
+pub use autopromote::{spawn_autopromote_loop, AutopromoteParams};
+pub use crystallize::{detect_crystals, Crystal, CrystallizationParams};
+pub use dispatch::{dispatch_actions, ActionSink, NullSink};
+pub use engine::{EventKindDiscriminant, RuleEngine, SubjectInfo};
+pub use introspect::{IntrospectRequest, IntrospectResponse, IntrospectServer, BrainState};
+pub use loader::{load_card_file, load_rules_file};
+pub use metrics::serve_metrics;
+pub use observer::{Observer, TimedEvent};
+pub use rules::{Action, EventKind, EventPattern, LogLevel, Rule, Scope};