ticket: close panel startup e2e work

.yoi/tickets/00001KVDQH839/thread.md

@@ -4,4 +4,31 @@
 
 LocalTicketBackend によって作成されました。
 
+---
+
+<!-- event: state_changed author: hare at: 2026-06-19T05:44:09Z from: done to: closed reason: closed field: state -->
+
+## State changed
+
+Ticket を closed にしました。
+
+
+---
+
+<!-- event: close author: hare at: 2026-06-19T05:44:09Z status: closed -->
+
+## 完了
+
+Closed as completed.
+
+Added E2E coverage for a Panel shell-enter launch path:
+- PTY starts `/bin/sh` and sends `exec <yoi> panel ...` as the command line;
+- measurement starts immediately before sending the command line / Enter-equivalent input;
+- the test waits for the existing dashboard content-ready snapshot rather than first frame or a single row;
+- isolated HOME/XDG/runtime fixture remains in place and `YOI_POD_RUNTIME_COMMAND` is pinned to the tested binary;
+- direct-spawn Panel readiness tests remain as separate coverage.
+
+Validation was recorded during implementation, including the focused shell-enter test, the full Panel E2E test set, relevant cargo check, formatting, diff check, ticket doctor, and Nix build.
+
+
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