Add self-hosted RCS backend, extension, and ops tooling

Ship the Go/SQLite API and Web UI, Chrome/Brave capture addon,
Docker Compose, Pangolin reverse-proxy support, and a user-crontab
watchdog so the binary stays running without systemd.

extension/options/options.js

@@ -0,0 +1,102 @@
+const backendUrlInput = document.getElementById("backendUrl");
+const apiKeyInput = document.getElementById("apiKey");
+const msg = document.getElementById("msg");
+const blocklistEl = document.getElementById("blocklist");
+const blockUserInput = document.getElementById("blockUserInput");
+const blocklistStatus = document.getElementById("blocklistStatus");
+
+function renderBlocklist(usernames) {
+  blocklistEl.innerHTML = "";
+  if (!usernames.length) {
+    const empty = document.createElement("li");
+    empty.className = "muted";
+    empty.textContent = "No blocked authors.";
+    blocklistEl.appendChild(empty);
+    return;
+  }
+  usernames.forEach((name) => {
+    const li = document.createElement("li");
+    const label = document.createElement("span");
+    label.textContent = name;
+    const remove = document.createElement("button");
+    remove.type = "button";
+    remove.textContent = "Remove";
+    remove.addEventListener("click", async () => {
+      blocklistStatus.textContent = "Syncing…";
+      try {
+        const list = await rcsRemoveBlocked(name);
+        renderBlocklist(list);
+        blocklistStatus.textContent = "Synced";
+      } catch (err) {
+        blocklistStatus.textContent = String(err && err.message ? err.message : err);
+        blocklistStatus.classList.add("error");
+      }
+    });
+    li.appendChild(label);
+    li.appendChild(remove);
+    blocklistEl.appendChild(li);
+  });
+}
+
+async function syncBlocklist() {
+  blocklistStatus.classList.remove("error");
+  blocklistStatus.textContent = "Syncing…";
+  try {
+    const list = await rcsPullBlocklist();
+    renderBlocklist(list);
+    blocklistStatus.textContent = `Synced (${list.length})`;
+  } catch (err) {
+    const cached = await rcsGetCachedBlocklist();
+    renderBlocklist(cached);
+    blocklistStatus.textContent = "Sync failed — showing cache. " + (err && err.message ? err.message : err);
+    blocklistStatus.classList.add("error");
+  }
+}
+
+chrome.storage.sync.get({ backendUrl: "", apiKey: "" }, (settings) => {
+  backendUrlInput.value = settings.backendUrl || "";
+  apiKeyInput.value = settings.apiKey || "";
+  if (settings.backendUrl) {
+    syncBlocklist();
+  } else {
+    rcsGetCachedBlocklist().then(renderBlocklist);
+  }
+});
+
+document.getElementById("save").addEventListener("click", async () => {
+  const backendUrl = backendUrlInput.value.trim().replace(/\/+$/, "");
+  const apiKey = apiKeyInput.value.trim();
+  try {
+    if (backendUrl) new URL(backendUrl);
+  } catch {
+    msg.textContent = "Invalid URL";
+    return;
+  }
+  if (backendUrl) {
+    try {
+      const origin = new URL(backendUrl).origin + "/*";
+      await chrome.permissions.request({ origins: [origin] });
+    } catch {
+      // ignore
+    }
+  }
+  await chrome.storage.sync.set({ backendUrl, apiKey });
+  msg.textContent = "Saved.";
+  if (backendUrl) await syncBlocklist();
+});
+
+document.getElementById("blockAdd").addEventListener("click", async () => {
+  const username = blockUserInput.value.trim();
+  if (!username) return;
+  blocklistStatus.classList.remove("error");
+  blocklistStatus.textContent = "Syncing…";
+  try {
+    const list = await rcsAddBlocked(username);
+    blockUserInput.value = "";
+    renderBlocklist(list);
+    blocklistStatus.textContent = "Synced";
+  } catch (err) {
+    blocklistStatus.textContent = String(err && err.message ? err.message : err);
+    blocklistStatus.classList.add("error");
+  }
+});