feat(supply-api): persist audit alerts

supply-api/sql/postgresql/audit_alerts_v1.sql

@@ -0,0 +1,41 @@
+-- 审计告警持久化表
+-- 用途：为 /api/v1/audit/alerts 提供 PostgreSQL-backed 存储，避免 HTTP 层固定回退到内存实现。
+
+CREATE TABLE IF NOT EXISTS audit_alerts (
+    alert_id TEXT PRIMARY KEY,
+    alert_name TEXT NOT NULL DEFAULT '',
+    alert_type TEXT NOT NULL,
+    alert_level TEXT NOT NULL,
+    tenant_id BIGINT NOT NULL,
+    supplier_id BIGINT,
+    title TEXT NOT NULL,
+    message TEXT NOT NULL DEFAULT '',
+    description TEXT NOT NULL DEFAULT '',
+    event_id TEXT,
+    event_ids JSONB NOT NULL DEFAULT '[]'::jsonb,
+    trigger_condition TEXT NOT NULL DEFAULT '',
+    threshold DOUBLE PRECISION NOT NULL DEFAULT 0,
+    current_value DOUBLE PRECISION NOT NULL DEFAULT 0,
+    status TEXT NOT NULL,
+    resolved_at TIMESTAMPTZ,
+    resolved_by TEXT,
+    resolve_note TEXT,
+    notify_enabled BOOLEAN NOT NULL DEFAULT TRUE,
+    notify_channels JSONB NOT NULL DEFAULT '[]'::jsonb,
+    created_at TIMESTAMPTZ NOT NULL,
+    updated_at TIMESTAMPTZ NOT NULL,
+    first_seen_at TIMESTAMPTZ NOT NULL,
+    last_seen_at TIMESTAMPTZ NOT NULL,
+    metadata JSONB NOT NULL DEFAULT '{}'::jsonb,
+    tags JSONB NOT NULL DEFAULT '[]'::jsonb
+);
+
+CREATE INDEX IF NOT EXISTS idx_audit_alerts_tenant_status_created_at
+    ON audit_alerts (tenant_id, status, created_at DESC);
+
+CREATE INDEX IF NOT EXISTS idx_audit_alerts_tenant_type_level
+    ON audit_alerts (tenant_id, alert_type, alert_level);
+
+CREATE INDEX IF NOT EXISTS idx_audit_alerts_supplier_created_at
+    ON audit_alerts (supplier_id, created_at DESC)
+    WHERE supplier_id IS NOT NULL;