feat(ui,docs): Agent 流式侧栏 + 结果区/MCP 点/确认条 + 官网文案

- 侧栏消费 Agent SSE：时间线边 append、正文 ▌、停止按钮
- 「在结果区打开」不抢编辑器 focus；MCP 活跃点；写操作确认条
- 文档/落地页补充 Ask|Agent 与 npx @rlwj-lab/opsxdb-mcp（不宣传默认可写）

src/api.ts

@@ -552,6 +552,149 @@ export async function callAiAgent(payload: {
   return post<AiAgentRes>("/api/ai/agent", payload);
 }
 
+export type AiAgentQueryResult = {
+  columns: string[];
+  rows: Record<string, unknown>[];
+  rowCount: number;
+  sql?: string;
+  tool?: string;
+};
+
+export type AiAgentStepExt = AiAgentStep & {
+  pending?: boolean;
+  needConfirm?: boolean;
+  confirmSql?: string;
+  result?: AiAgentQueryResult;
+};
+
+export type AiAgentStreamHandlers = {
+  onStepStart?: (step: AiAgentStepExt) => void;
+  onStep?: (step: AiAgentStepExt) => void;
+  onDelta?: (delta: string) => void;
+  onDone?: (res: AiAgentRes) => void;
+  onError?: (error: string, partial?: Partial<AiAgentRes>) => void;
+};
+
+/** Agent SSE（stream=true）；不可用时回落非流式。signal 供「停止」。 */
+export async function callAiAgentStream(
+  payload: {
+    prompt: string;
+    connectionId?: string;
+    driver?: string;
+    database?: string;
+    model?: string;
+  },
+  handlers: AiAgentStreamHandlers,
+  signal?: AbortSignal,
+): Promise<AiAgentRes> {
+  try {
+    const res = await fetch(`${API}/api/ai/agent`, {
+      method: "POST",
+      headers: {
+        "Content-Type": "application/json",
+        Accept: "text/event-stream",
+        ...authHeaders(),
+      },
+      body: JSON.stringify({ ...payload, stream: true }),
+      signal,
+    });
+    if (!res.ok || !res.body || !(res.headers.get("content-type") || "").includes("text/event-stream")) {
+      const plain = await callAiAgent(payload);
+      handlers.onDone?.(plain);
+      return plain;
+    }
+    const reader = res.body.getReader();
+    const dec = new TextDecoder();
+    let buf = "";
+    let content = "";
+    const steps: AiAgentStep[] = [];
+    let rounds = 0;
+    let finalRes: AiAgentRes | null = null;
+
+    const handleEvent = (event: string, data: string) => {
+      let ev: Record<string, unknown>;
+      try {
+        ev = JSON.parse(data) as Record<string, unknown>;
+      } catch {
+        return;
+      }
+      const typ = event || String(ev.type || "");
+      if (typ === "step_start" && ev.step) {
+        handlers.onStepStart?.(ev.step as AiAgentStepExt);
+      } else if (typ === "step" && ev.step) {
+        const st = ev.step as AiAgentStepExt;
+        steps.push(st);
+        handlers.onStep?.(st);
+      } else if (typ === "delta") {
+        const d = String(ev.delta || "");
+        content += d;
+        handlers.onDelta?.(d);
+      } else if (typ === "done") {
+        finalRes = {
+          content: String(ev.content ?? content),
+          sql: ev.sql ? String(ev.sql) : undefined,
+          steps: (ev.steps as AiAgentStep[]) || steps,
+          rounds: Number(ev.rounds ?? rounds) || 0,
+        };
+        rounds = finalRes.rounds;
+        handlers.onDone?.(finalRes);
+      } else if (typ === "error") {
+        handlers.onError?.(String(ev.error || "agent error"), { content, steps, rounds: Number(ev.rounds) || 0 });
+      }
+    };
+
+    while (true) {
+      const { done, value } = await reader.read();
+      if (done) break;
+      buf += dec.decode(value, { stream: true });
+      let idx: number;
+      while ((idx = buf.indexOf("\n\n")) >= 0) {
+        const chunk = buf.slice(0, idx);
+        buf = buf.slice(idx + 2);
+        let event = "";
+        let data = "";
+        for (const line of chunk.split("\n")) {
+          if (line.startsWith("event:")) event = line.slice(6).trim();
+          else if (line.startsWith("data:")) data += (data ? "\n" : "") + line.slice(5).trim();
+        }
+        if (data) handleEvent(event, data);
+      }
+    }
+    if (finalRes) return finalRes;
+    const fallback: AiAgentRes = { content, steps, rounds };
+    handlers.onDone?.(fallback);
+    return fallback;
+  } catch (e) {
+    if (signal?.aborted) throw e;
+    const plain = await callAiAgent(payload);
+    handlers.onDone?.(plain);
+    return plain;
+  }
+}
+
+export type McpStatus = {
+  configured: boolean;
+  mode: string;
+  whitelistCount: number;
+  writesEnabled: boolean;
+  active: boolean;
+  recent?: { time: string; tool: string; ok: boolean; summary?: string; error?: string; source?: string }[];
+};
+
+export async function getMcpStatus(signal?: AbortSignal) {
+  return get<McpStatus>("/api/ai/mcp-status", signal);
+}
+
+export async function confirmAiAgentWrite(payload: {
+  connectionId: string;
+  sql?: string;
+  command?: string;
+  database?: string;
+  kind?: "query" | "redis";
+}) {
+  return post<Record<string, unknown>>("/api/ai/agent/confirm", payload);
+}
+
 /** C4:AI 配置(key 脱敏,只回掩码与是否已配置);protocol/authStyle/allowInsecureHttp 见 aiPresets.ts */
 export type AiConfig = {
   provider: string;