feat(httpapi): add local audit log with portal dual-write

Локальный audit_log (миграции pg/sqlite), GET /v1/audit, запись на CRUD и async push в auth-portal (source_app=bgp).

Co-authored-by: Cursor <[email protected]>

migrations/postgres/000030_audit_log.down.sql

@@ -0,0 +1,4 @@
+DROP INDEX IF EXISTS idx_audit_log_tenant_action;
+DROP INDEX IF EXISTS idx_audit_log_tenant_created;
+DROP INDEX IF EXISTS idx_audit_log_event_id;
+DROP TABLE IF EXISTS audit_log;

migrations/postgres/000030_audit_log.up.sql

@@ -0,0 +1,30 @@
+CREATE TABLE IF NOT EXISTS audit_log (
+    id TEXT PRIMARY KEY,
+    tenant_id TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    source_app TEXT NOT NULL DEFAULT 'bgp',
+    action TEXT NOT NULL,
+    severity TEXT NOT NULL DEFAULT 'info',
+    actor_user_id TEXT,
+    actor_email TEXT,
+    actor_name TEXT,
+    actor_api_key_prefix TEXT,
+    target_type TEXT,
+    target_id TEXT,
+    summary TEXT NOT NULL,
+    details_json JSONB,
+    ip TEXT,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
+    portal_pushed_at TIMESTAMPTZ,
+    CONSTRAINT audit_log_severity_chk CHECK (severity IN ('info', 'warning', 'critical')),
+    CONSTRAINT audit_log_source_app_chk CHECK (source_app = 'bgp'),
+    CONSTRAINT audit_log_summary_chk CHECK (length(trim(summary)) > 0)
+);
+
+CREATE UNIQUE INDEX IF NOT EXISTS idx_audit_log_event_id ON audit_log (event_id);
+
+CREATE INDEX IF NOT EXISTS idx_audit_log_tenant_created
+    ON audit_log (tenant_id, created_at DESC);
+
+CREATE INDEX IF NOT EXISTS idx_audit_log_tenant_action
+    ON audit_log (tenant_id, action, created_at DESC);