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/components/run/LaneConsolePane.tsx

@@ -129,7 +129,6 @@ export function LaneConsolePane({
   useEffect(() => {
     const { activeRuns: runs } = latest.current;
     setPrompt("");
-    lastPrefill.current = "";
     setResumeSession(null);
     setError(null);
     setBusy(null);
@@ -138,34 +137,10 @@ export function LaneConsolePane({
     refreshList();
   }, [laneId, refreshList]);
 
-  // Pre-fill the prompt with the slash command the lane's pipeline template
-  // names as its driver, so picking the 16-node pipeline starts the 16-step
-  // skill and the 8-node one the 8-step skill. Only overwrites a prompt the
-  // user hasn't touched (still exactly the previous prefill), so switching
-  // templates never eats a typed requirement. Must be declared AFTER the
-  // lane-switch effect: on a lane change that one clears both first.
-  const lastPrefill = useRef("");
-  // Claude gets a slash command it can execute (`pipeline_skill`), which itself
-  // declares stage at every step. Codex has no slash commands — the same
-  // string would read as literal prose — so it gets the equivalent priming a
-  // different way: a plain-text checklist of this lane's own pipeline node ids,
-  // read directly off `pipeline_nodes` so it always matches the template in
-  // use. Without SOME opening nudge a codex lane's declared stage depends
-  // entirely on AGENTS.md being read on its own, which is easy to miss.
-  const promptPrefill =
-    laneTool === "codex"
-      ? currentLane?.pipeline_nodes?.length
-        ? `Declare progress as you go: run \`agenthub stage <stage> --tool codex --evidence "..."\` immediately at each real transition through this pipeline — ${currentLane.pipeline_nodes.map((n) => n.id).join(" -> ")}. Then, your task:\n\n`
-        : ""
-      : currentLane?.pipeline_skill || "";
-  useEffect(() => {
-    const next = promptPrefill && laneTool === "claude" ? `${promptPrefill} ` : promptPrefill;
-    setPrompt((p) => (p === lastPrefill.current ? next : p));
-    lastPrefill.current = next;
-    // `laneId` is a dep too: switching between two lanes on the SAME template
-    // leaves `promptPrefill` unchanged, and the switch effect just cleared the
-    // prompt — without it the new lane would open with an empty box.
-  }, [promptPrefill, laneTool, laneId]);
+  // Picking a pipeline template writes NOTHING into the prompt box: a prefilled
+  // slash command (or the codex stage-checklist prose) is sent as soon as the
+  // run starts, which is an extra prompt nobody asked for. The prompt is the
+  // user's to type; the pipeline is declared by `agenthub stage` instead.
 
   // The switch effect above only sees whatever `activeRuns` the page already
   // had loaded at that instant. Remounting this page (navigating away and