feat(admin): 运营后台（登录/查看/审核编辑/补全）+ 写入API + 审计留痕

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

migrations/0005_admin.up.sql

@@ -0,0 +1,22 @@
+-- Admin console support: manual edit provenance + audit log.
+
+-- Manual-entry source used to record field-level provenance for operator edits.
+INSERT INTO source (name, homepage, license, trust_weight, notes)
+VALUES ('manual', NULL, 'proprietary', 0.90, '运营人工录入/补全')
+ON CONFLICT (name) DO NOTHING;
+
+-- Audit trail: every admin write records actor, action, entity and before/after.
+CREATE TABLE IF NOT EXISTS audit_log (
+    id         UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    actor      TEXT NOT NULL,
+    action     TEXT NOT NULL,
+    entity     TEXT NOT NULL,
+    entity_id  UUID,
+    fields     TEXT[] NOT NULL DEFAULT '{}',
+    before     JSONB,
+    after      JSONB,
+    created_at TIMESTAMPTZ NOT NULL DEFAULT now()
+);
+
+CREATE INDEX IF NOT EXISTS idx_audit_entity ON audit_log (entity, entity_id);
+CREATE INDEX IF NOT EXISTS idx_audit_created ON audit_log (created_at DESC);