feat(docs): add README.md button opening shared doc drawer

Reuses the existing API.md drawer for README; switching between
docs reloads content and updates the drawer title. Backend serves
README.md via /api/docs/readme-md.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/handler/doc.rs

@@ -21,3 +21,20 @@ pub async fn get_api_md() -> Result<impl IntoResponse, ApiErr> {
 
     Ok((StatusCode::OK, headers, content))
 }
+
+pub async fn get_readme_md() -> Result<impl IntoResponse, ApiErr> {
+    let content = tokio::fs::read_to_string("README.md")
+        .await
+        .map_err(|err| {
+            tracing::error!("Failed to read README.md: {}", err);
+            ApiErr::NotFound("README.md not found".to_string(), None)
+        })?;
+
+    let mut headers = HeaderMap::new();
+    headers.insert(
+        header::CONTENT_TYPE,
+        HeaderValue::from_static("text/markdown; charset=utf-8"),
+    );
+
+    Ok((StatusCode::OK, headers, content))
+}

src/main.rs

@@ -280,7 +280,8 @@ fn build_router(state: AppState) -> Router {
         )
         .route("/api/logs", get(handler::log::get_logs))
         .route("/api/logs/stream", get(handler::log::stream_logs))
-        .route("/api/docs/api-md", get(handler::doc::get_api_md));
+        .route("/api/docs/api-md", get(handler::doc::get_api_md))
+        .route("/api/docs/readme-md", get(handler::doc::get_readme_md));
 
     Router::new()
         .merge(all_route)

web/html/topbar.html

@@ -5,6 +5,7 @@
     <button type="button" class="tab-btn" id="tabConfig">配置</button>
   </div>
   <div class="topbar-actions">
+    <button type="button" class="secondary" id="openReadmeDoc">README.md</button>
     <button type="button" class="secondary" id="openApiDoc">API.md</button>
     <div class="status" id="statusText">
       <span class="ws-dot" id="wsDot"></span>

web/js/app.js

@@ -1,7 +1,7 @@
 import { withStatus } from "./api.js";
 import { openChart, renderChart } from "./chart.js";
 import { dom } from "./dom.js";
-import { closeApiDocDrawer, openApiDocDrawer } from "./docs.js";
+import { closeApiDocDrawer, openApiDocDrawer, openReadmeDrawer } from "./docs.js";
 import { loadEvents } from "./events.js";
 import {
   applyBatchEquipmentUnit,
@@ -130,6 +130,7 @@ function bindEvents() {
     });
   });
 
+  dom.openReadmeDocBtn.addEventListener("click", () => withStatus(openReadmeDrawer()));
   dom.openApiDocBtn.addEventListener("click", () => withStatus(openApiDocDrawer()));
   dom.closeApiDocBtn.addEventListener("click", closeApiDocDrawer);
   dom.refreshEventBtn.addEventListener("click", () => withStatus(loadEvents()));

web/js/docs.js

@@ -82,11 +82,11 @@ function parseMarkdown(text) {
   return { html: blocks.join(""), headings };
 }
 
-export async function loadApiDoc() {
+async function loadDoc(url, emptyMessage) {
-  const text = await apiFetch("/api/docs/api-md");
+  const text = await apiFetch(url);
   const { html, headings } = parseMarkdown(text || "");
 
-  dom.apiDocContent.innerHTML = html || "<p>API.md 为空</p>";
+  dom.apiDocContent.innerHTML = html || `<p>${emptyMessage}</p>`;
   dom.apiDocToc.innerHTML = headings.length
     ? headings
         .map(
@@ -110,14 +110,25 @@ export async function loadApiDoc() {
       }
     });
   });
-
-  state.apiDocLoaded = true;
 }
 
 export async function openApiDocDrawer() {
+  const title = dom.apiDocDrawer.querySelector("h3");
+  if (title) title.textContent = "API.md";
   dom.apiDocDrawer.classList.remove("hidden");
-  if (!state.apiDocLoaded) {
+  if (state.docDrawerSource !== "api") {
-    await loadApiDoc();
+    state.docDrawerSource = "api";
+    await loadDoc("/api/docs/api-md", "API.md 为空");
+  }
+}
+
+export async function openReadmeDrawer() {
+  const title = dom.apiDocDrawer.querySelector("h3");
+  if (title) title.textContent = "README.md";
+  dom.apiDocDrawer.classList.remove("hidden");
+  if (state.docDrawerSource !== "readme") {
+    state.docDrawerSource = "readme";
+    await loadDoc("/api/docs/readme-md", "README.md 为空");
   }
 }
 

web/js/dom.js

@@ -81,6 +81,7 @@ export const dom = {
   batchBindingSignalRole: byId("batchBindingSignalRole"),
   apiDocToc: byId("apiDocToc"),
   apiDocContent: byId("apiDocContent"),
+  openReadmeDocBtn: byId("openReadmeDoc"),
   openApiDocBtn: byId("openApiDoc"),
   closeApiDocBtn: byId("closeApiDoc"),
   refreshChartBtn: byId("refreshChart"),

web/js/state.js

@@ -19,7 +19,7 @@ export const state = {
   chartPointName: "",
   chartData: [],
   pointSocket: null,
-  apiDocLoaded: false,
+  docDrawerSource: null,  // null | "api" | "readme"
   runtimes: new Map(),  // unit_id -> UnitRuntime
   activeView: "ops",   // "ops" | "config"
   opsPointEls: new Map(),    // point_id -> { pillEl, syncBtns? }