feat: add audit_log_national table [D109] Layer 3 append-only national audit chain

persona-brain-db/schema/12-audit-log-national.sql

@@ -0,0 +1,24 @@
+-- ============================================================
+-- 表12：audit_log_national（审计日志 · 国家操作 · append-only）
+-- 用途：国家系统级别的操作审计，完全透明，不可篡改
+-- Hash chain：每行包含上一行的checksum形成链式结构
+-- ============================================================
+
+CREATE TABLE IF NOT EXISTS audit_log_national (
+  log_id            INTEGER       PRIMARY KEY AUTOINCREMENT,
+  operation         VARCHAR(64)   NOT NULL,
+  actor             VARCHAR(64)   NOT NULL,
+  target_type       VARCHAR(32),
+  target_id         VARCHAR(64),
+  details           TEXT,                          -- JSON object
+  ip_address        VARCHAR(45),
+  result            VARCHAR(16)   NOT NULL
+                    CHECK (result IN ('success', 'failure', 'pending')),
+  checksum          VARCHAR(128),                   -- hash chain for append-only integrity
+  prev_log_id       INTEGER       REFERENCES audit_log_national(log_id),
+  timestamp         TIMESTAMP     NOT NULL DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE INDEX IF NOT EXISTS idx_aln_operation ON audit_log_national(operation);
+CREATE INDEX IF NOT EXISTS idx_aln_actor ON audit_log_national(actor);
+CREATE INDEX IF NOT EXISTS idx_aln_timestamp ON audit_log_national(timestamp);