feat: Stop archives a session, Sleep keeps it; SSH keys per type (#82); update Auto fix

- Stop (a tab's or pane's X, Close tab) now archives the session it held
  (DELETE /api/run/:id?archive=1); the new Sleep (moon left of the X, and in
  the tab, pane and session right-click menus) stops the pane but keeps the
  session listed to resume later. Shared endRuns in client/src/lib/stopSession.ts.
- Git identity (#82): an account keeps an ED25519 AND an RSA key (AWS
  CodeCommit takes only RSA), every ssh git offers both, and a member's
  ~/.gitconfig gets core.sshCommand so a git typed in a terminal uses them.
- Update dialog: Auto fix starts a Claude Code session on the install
  folder with the failed update's error.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/__tests__/run.test.js

@@ -173,6 +173,34 @@ describe("/api/run", () => {
     assert.deepEqual(body, { ok: true });
   });
 
+  it("DELETE /:id?archive=1 archives the run's session; a plain DELETE (Sleep) keeps it", async () => {
+    const { db } = require("../db");
+    db.prepare("INSERT INTO sessions (id, cwd) VALUES (?, ?)").run("sess-stop", TMP);
+    db.prepare("INSERT INTO sessions (id, cwd) VALUES (?, ?)").run("sess-sleep", TMP);
+    const run = db.prepare(
+      "INSERT OR REPLACE INTO dashboard_runs (id, session_id, cwd, status) VALUES (?, ?, ?, 'running')"
+    );
+    const archivedAt = (id) =>
+      db.prepare("SELECT archived_at FROM sessions WHERE id = ?").get(id).archived_at;
+    tmux.__setExecImpl(() => "");
+
+    run.run("agenthub-lane-9-1", "sess-sleep", TMP);
+    const slept = await fetchJson("/api/run/agenthub-lane-9-1", { method: "DELETE" });
+    assert.deepEqual(slept.body, { ok: true });
+    assert.equal(archivedAt("sess-sleep"), null);
+
+    run.run("agenthub-lane-9-2", "sess-stop", TMP);
+    const stopped = await fetchJson("/api/run/agenthub-lane-9-2?archive=1", { method: "DELETE" });
+    assert.equal(stopped.status, 200);
+    assert.deepEqual(stopped.body, { ok: true, archived: "sess-stop" });
+    assert.ok(archivedAt("sess-stop"));
+
+    // A pane with no known session (a shell) archives nothing.
+    run.run("agenthub-lane-9-3", null, TMP);
+    const shell = await fetchJson("/api/run/agenthub-lane-9-3?archive=1", { method: "DELETE" });
+    assert.deepEqual(shell.body, { ok: true, archived: null });
+  });
+
   it("DELETE /:id returns 404 for a session that doesn't exist", async () => {
     tmux.__setExecImpl((args) => {
       if (args[0] === "has-session") {