fix(cli): agents webhook-secret regenerate sends X-Confirm-Destructive header (Bug cmp03hy9o) (#47)

`cueapi agents webhook-secret regenerate <ref>` was making the
POST /v1/agents/{ref}/webhook-secret/regenerate request without
the `X-Confirm-Destructive: true` header that the server requires.
Result: even after the user typed `y` at the confirmation prompt,
the request was rejected HTTP 400 server-side.

Surfaced 2026-05-10 from Phase 2 messaging smoke testing —
identical bug shape to the one already fixed on
`cueapi key webhook-secret regenerate` (which did pass the header).

Mirror the existing pattern: pass the header on the httpx POST
right after the Y/N confirm clears.

Tests:
- New `test_agents_webhook_secret_regenerate_sends_destructive_header`
  pins the header on the wire — same shape as the existing
  `test_key_webhook_secret_regenerate_sends_destructive_header`.

Author: mikemolinet

cueapi/cli.py

@@ -1662,7 +1662,11 @@ def agents_webhook_secret_regenerate(ctx: click.Context, ref: str, yes: bool) ->
             return
     try:
         with CueAPIClient(api_key=ctx.obj.get("api_key"), profile=ctx.obj.get("profile")) as client:
-            resp = client.post(f"/agents/{ref}/webhook-secret/regenerate", json={})
+            resp = client.post(
+                f"/agents/{ref}/webhook-secret/regenerate",
+                json={},
+                headers={"X-Confirm-Destructive": "true"},
+            )
             if resp.status_code == 200:
                 data = resp.json()
                 click.echo()

tests/test_cli.py

@@ -682,6 +682,34 @@ def test_agents_webhook_secret_regenerate_with_yes(monkeypatch):
     assert "save now" in result.output.lower() or "shown once" in result.output.lower()
 
 
+def test_agents_webhook_secret_regenerate_sends_destructive_header(monkeypatch):
+    """Pin: `cueapi agents webhook-secret regenerate` MUST send
+    `X-Confirm-Destructive: true` header — server requires it (Bug
+    cmp03hy9o, surfaced 2026-05-10 from Phase 2 messaging smoke).
+    Mirrors the same header pin on `cueapi key webhook-secret regenerate`.
+    """
+    holder: dict = {}
+    _patch_ws_client(
+        monkeypatch,
+        holder,
+        responses={
+            ("POST", "/agents/agt_x/webhook-secret/regenerate"): lambda: _FakeResp(
+                200, {"webhook_secret": "wsec_new"}
+            )
+        },
+    )
+    result = runner.invoke(
+        main,
+        ["agents", "webhook-secret", "regenerate", "agt_x", "--yes"],
+    )
+    assert result.exit_code == 0, result.output
+    method, path, body, headers = holder["client"].calls[-1]
+    assert method == "POST"
+    assert path == "/agents/agt_x/webhook-secret/regenerate"
+    assert headers == {"X-Confirm-Destructive": "true"}
+    assert "wsec_new" in result.output
+
+
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