fix(run): plumb the recorded prompt back into live runs, fix lane routing when the cwd doesn't match the selected lane

- pty-run.js's publicRun() now reads promptPreview back from the
  dashboard_runs row it already wrote at spawn time (was persisted,
  never read back) — RunHandle carries it through to the client.
- Workspace.tsx's onStartFromSetup no longer trusts RunSetup's
  always-populated laneId prop to decide whether a new lane needs
  ensuring — it re-resolves the target lane from the cwd the user
  actually typed, so starting a run with a different cwd than the
  currently-selected lane correctly ensures/creates the right lane
  instead of silently starting in the wrong one.

Fixes findings from the Task 8+9+10 review that a prior fix attempt
left unresolved (2f39f4e's --no-verify commit, and an incomplete
diagnosis of the lane-routing bug as a test-harness artifact).

server/__tests__/pty-run.test.js

@@ -135,4 +135,32 @@ describe("pty-run", () => {
     assert.equal(pty.laneIdFromRunId("ccam-lane-42"), 42);
     assert.equal(pty.laneIdFromRunId("not-a-run-id"), null);
   });
+
+  it("getRun returns the recorded prompt for a live run", () => {
+    let sessionExists = false;
+    tmux.__setExecImpl((args) => {
+      if (args[0] === "has-session") {
+        if (sessionExists) {
+          return ""; // session exists
+        }
+        // Session doesn't exist yet
+        const e = new Error("no such session");
+        e.status = 1;
+        throw e;
+      }
+      if (args[0] === "new-session") {
+        sessionExists = true; // Mark session as created
+      }
+      return "";
+    });
+    const handle = pty.spawnRun({
+      laneId: 99,
+      cwd: "/tmp/test",
+      initialPrompt: "the live prompt",
+    });
+    const retrieved = pty.getRun(handle.id);
+    assert.equal(retrieved.id, "ccam-lane-99");
+    assert.equal(retrieved.promptPreview, "the live prompt");
+    assert.equal(retrieved.status, "running");
+  });
 });