docs(agent): 补全会话与对话设计

script/sql/agent_session.sql

@@ -0,0 +1,44 @@
+-- Agent 会话与消息表。
+
+CREATE TABLE IF NOT EXISTS agent_session (
+    id BIGSERIAL PRIMARY KEY,
+    session_code VARCHAR(100) NOT NULL,
+    agent_id BIGINT NOT NULL,
+    workflow_run_id BIGINT,
+    title VARCHAR(200),
+    status VARCHAR(50) NOT NULL DEFAULT 'ACTIVE',
+    metadata_json JSONB NOT NULL DEFAULT '{}'::jsonb,
+    version INTEGER NOT NULL DEFAULT 1,
+    create_time TIMESTAMP,
+    update_time TIMESTAMP,
+    remark VARCHAR(500) DEFAULT '',
+    create_by VARCHAR(64),
+    update_by VARCHAR(64),
+    CONSTRAINT uk_agent_session_code UNIQUE (session_code),
+    CONSTRAINT fk_agent_session_agent_id FOREIGN KEY (agent_id) REFERENCES agent_definition (id),
+    CONSTRAINT fk_agent_session_run_id FOREIGN KEY (workflow_run_id) REFERENCES workflow_run (id)
+);
+
+CREATE TABLE IF NOT EXISTS agent_message (
+    id BIGSERIAL PRIMARY KEY,
+    session_id BIGINT NOT NULL,
+    role VARCHAR(50) NOT NULL,
+    content TEXT NOT NULL,
+    citation_json JSONB NOT NULL DEFAULT '[]'::jsonb,
+    token_count INTEGER,
+    version INTEGER NOT NULL DEFAULT 1,
+    create_time TIMESTAMP,
+    update_time TIMESTAMP,
+    remark VARCHAR(500) DEFAULT '',
+    create_by VARCHAR(64),
+    update_by VARCHAR(64),
+    CONSTRAINT fk_agent_message_session_id FOREIGN KEY (session_id) REFERENCES agent_session (id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_agent_session_agent_id ON agent_session (agent_id);
+CREATE INDEX IF NOT EXISTS idx_agent_session_status ON agent_session (status);
+CREATE INDEX IF NOT EXISTS idx_agent_message_session_id ON agent_message (session_id);
+CREATE INDEX IF NOT EXISTS idx_agent_message_role ON agent_message (role);
+
+COMMENT ON TABLE agent_session IS 'Agent会话表';
+COMMENT ON TABLE agent_message IS 'Agent消息表';