feat: executions, assertions y bucle reactivo en fn_operations

Añade Execution, Assertion, AssertionResult al paquete fn_operations.
Motor de evaluación de assertions con reescritura SQL automática.
Bucle reactivo: ExecuteAndReact evalúa assertions y cambia status de
entities (corrupted/stale) + auto-crea proposals en registry.
CLI fn ops: assertion (add/list/show/delete/eval) y execution (add/list/show).
Migración 002_executions_assertions.sql con FTS para assertions.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

fn_operations/migrations/002_executions_assertions.sql

@@ -0,0 +1,65 @@
+-- Executions, assertions, and assertion_results tables.
+-- Closes the autonomous improvement loop: execute -> assert -> analyze.
+
+CREATE TABLE IF NOT EXISTS executions (
+	id          TEXT PRIMARY KEY,
+	pipeline_id TEXT NOT NULL,
+	relation_id TEXT NOT NULL DEFAULT '',
+	status      TEXT NOT NULL CHECK(status IN ('success','failure','partial')),
+	started_at  TEXT NOT NULL,
+	ended_at    TEXT,
+	duration_ms INTEGER,
+	records_in  INTEGER,
+	records_out INTEGER,
+	error       TEXT NOT NULL DEFAULT '',
+	metrics     TEXT NOT NULL DEFAULT '{}',
+	created_at  TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS assertions (
+	id          TEXT PRIMARY KEY,
+	entity_id   TEXT NOT NULL REFERENCES entities(id),
+	name        TEXT NOT NULL,
+	kind        TEXT NOT NULL,
+	rule        TEXT NOT NULL,
+	severity    TEXT NOT NULL DEFAULT 'warning' CHECK(severity IN ('critical','warning','info')),
+	description TEXT NOT NULL DEFAULT '',
+	active      INTEGER NOT NULL DEFAULT 1,
+	created_at  TEXT NOT NULL
+);
+
+CREATE TABLE IF NOT EXISTS assertion_results (
+	id           TEXT PRIMARY KEY,
+	assertion_id TEXT NOT NULL REFERENCES assertions(id),
+	execution_id TEXT NOT NULL DEFAULT '',
+	status       TEXT NOT NULL CHECK(status IN ('pass','fail','skip')),
+	value        TEXT NOT NULL DEFAULT '{}',
+	message      TEXT NOT NULL DEFAULT '',
+	evaluated_at TEXT NOT NULL
+);
+
+CREATE VIRTUAL TABLE IF NOT EXISTS assertions_fts USING fts5(
+	id,
+	name,
+	description,
+	rule,
+	content='assertions',
+	content_rowid='rowid'
+);
+
+CREATE TRIGGER IF NOT EXISTS assertions_ai AFTER INSERT ON assertions BEGIN
+	INSERT INTO assertions_fts(rowid, id, name, description, rule)
+	VALUES (new.rowid, new.id, new.name, new.description, new.rule);
+END;
+
+CREATE TRIGGER IF NOT EXISTS assertions_ad AFTER DELETE ON assertions BEGIN
+	INSERT INTO assertions_fts(assertions_fts, rowid, id, name, description, rule)
+	VALUES ('delete', old.rowid, old.id, old.name, old.description, old.rule);
+END;
+
+CREATE TRIGGER IF NOT EXISTS assertions_au AFTER UPDATE ON assertions BEGIN
+	INSERT INTO assertions_fts(assertions_fts, rowid, id, name, description, rule)
+	VALUES ('delete', old.rowid, old.id, old.name, old.description, old.rule);
+	INSERT INTO assertions_fts(rowid, id, name, description, rule)
+	VALUES (new.rowid, new.id, new.name, new.description, new.rule);
+END;