feat(run,notifications,profiles): stop sending prompts nobody typed, and fix notification + profile delivery

Run console:
- Picking a pipeline no longer pre-writes anything into the prompt box
  (`promptPrefill` in `LaneConsolePane.tsx` is gone — it wrote the driving
  slash command on a claude lane and a stage checklist on a codex one).
  Whatever sits in that box is sent as a real prompt the moment the run
  starts, so the box is the user's alone now.
- Resuming a session sends NO prompt at all (`handleStart` in `RunSetup.tsx`):
  the resumed session carries its own transcript, and leftover text in the box
  fired an extra turn into it.

Notifications:
- `client/src/lib/notify.ts` is now the ONE sender, used by both
  `useNotifications` and Settings' test button, and it reports where the
  notification landed: `POST /api/push/send` answering `{native:false,pushed:0}`
  means it went NOWHERE, so the client falls back to a local notification
  instead of counting the 200 as delivered.
- A notification carries the lane that raised it (`/workspace?lane=<id>`), and
  Workspace selects that lane on arrival.

Profiles:
- `server/lib/cc-profiles.js` reads and writes the macOS login Keychain item
  `Claude Code-credentials`, where the `claude` CLI actually keeps
  `claudeAiOauth` on darwin — a switch used to rewrite a file nothing reads.
  The file stays the fallback, is kept in step only when it already exists, and
  `AGENTHUB_CC_KEYCHAIN=0` pins it (tests set it).

Tests: npm run test:server (1820 pass), client vitest (553 pass).

client/src/pages/Settings.tsx

@@ -112,6 +112,7 @@ import { sagiPrefs } from "../components/Sagi/prefs";
 import { fmt, fmtCost, getCurrentLocale } from "../lib/format";
 import { subscribeToPush, unsubscribeFromPush } from "../lib/push";
 import { loadNotifPrefs, saveNotifPrefs, type NotifPrefs } from "../lib/notifPrefs";
+import { notify } from "../lib/notify";
 import { Tip } from "../components/Tip";
 import { ImportHistory } from "../components/ImportHistory";
 import { RemoteSources } from "../components/RemoteSources";
@@ -569,7 +570,10 @@ export function Settings() {
     const perm = await Notification.requestPermission();
     if (perm === "granted") {
       updateNotifPrefs({ enabled: true });
-      await subscribeToPush();
+      // A browser with no service worker / on a non-secure origin rejects here;
+      // notifications still work through the local fallback in useNotifications,
+      // so this must not blow up the enable flow.
+      await subscribeToPush().catch(() => {});
     }
   };
 
@@ -1554,14 +1558,6 @@ export function Settings() {
                     label={t("notifications.awaitingInput")}
                   />
                 </div>
-                <div className="flex items-center gap-3 bg-surface-2 rounded-lg px-3.5 py-3">
-                  <MessageSquare className="w-4 h-4 text-accent flex-shrink-0" />
-                  <Toggle
-                    checked={notifPrefs.onTurnComplete}
-                    onChange={(v) => updateNotifPrefs({ onTurnComplete: v })}
-                    label={t("notifications.turnComplete")}
-                  />
-                </div>
                 <div className="flex items-center gap-3 bg-surface-2 rounded-lg px-3.5 py-3">
                   <Play className="w-4 h-4 text-status-success flex-shrink-0" />
                   <Toggle
@@ -1570,6 +1566,14 @@ export function Settings() {
                     label={t("notifications.newSession")}
                   />
                 </div>
+                <div className="flex items-center gap-3 bg-surface-2 rounded-lg px-3.5 py-3">
+                  <MessageSquare className="w-4 h-4 text-accent flex-shrink-0" />
+                  <Toggle
+                    checked={notifPrefs.onTurnComplete}
+                    onChange={(v) => updateNotifPrefs({ onTurnComplete: v })}
+                    label={t("notifications.turnComplete")}
+                  />
+                </div>
                 <div className="flex items-center gap-3 bg-surface-2 rounded-lg px-3.5 py-3">
                   <CheckCircle className="w-4 h-4 text-violet-400 flex-shrink-0" />
                   <Toggle
@@ -1599,15 +1603,27 @@ export function Settings() {
               <div className="pt-3 border-t border-border">
                 <button
                   onClick={async () => {
-                    if (!("Notification" in window) || Notification.permission !== "granted")
-                      return;
-                    await fetch("/api/push/send", {
-                      method: "POST",
-                      headers: { "Content-Type": "application/json" },
-                      body: JSON.stringify({
-                        title: t("notifications.testTitle"),
-                        body: t("notifications.testBody"),
-                      }),
+                    // Same notify() the live events use, so the test proves the
+                    // real path — and reports WHERE it landed, since a push that
+                    // reaches nobody used to look exactly like success.
+                    const r = await notify(
+                      t("notifications.testTitle"),
+                      t("notifications.testBody")
+                    );
+                    const reason = r.errors
+                      .map((e) => [e.statusCode, e.message].filter(Boolean).join(" "))
+                      .join("; ");
+                    setActionResult({
+                      key: "notif-test",
+                      isError: r.via === "none" || r.via === "blocked",
+                      message:
+                        r.via === "push" || r.via === "native"
+                          ? t("notifications.testSent")
+                          : r.via === "local"
+                            ? t("notifications.testLocal")
+                            : r.via === "blocked"
+                              ? t("notifications.testBlocked")
+                              : `${t("notifications.testFailed")}${reason ? ` (${reason})` : ""}`,
                     });
                   }}
                   className="inline-flex items-center gap-1.5 text-xs px-3 py-1.5 rounded-md text-fg-secondary hover:text-fg-primary hover:bg-surface-4 border border-border transition-colors"
@@ -1615,6 +1631,7 @@ export function Settings() {
                   <Zap className="w-3 h-3" />
                   {t("notifications.sendTest")}
                 </button>
+                <div className="mt-2">{actionBanner(["notif-test"])}</div>
               </div>
             </div>
           )}