emrg: fix GUI task form empty dropdowns on quick add (rant 2026-08-14T15:41:52)

[argszero]

Host reported (rant 2026-08-14T15:41:52): in task management, clicking "＋ Add Task" then "Save Task" appears to do nothing.

Root cause (reproduced in headless Chrome against the real v0.2.36 renderer):
Race between openTaskForm and loadTaskMeta. The sidebar ⏱ nav handler calls openTasksPanel() fire-and-forget; openTaskForm synchronously reads the taskTypes/taskProjects globals while the taskTemplateList/listProjects IPC is still in flight → both dropdowns render 0 options → type/project are empty on save → main.js validation throws "invalid task type" → the error only lands in the chat area, so the UI looks unresponsive.

Fix (emrg/gui/renderer/js/dialogs.js):

• openTaskForm is now async and awaits loadTaskMeta() when the metadata globals are still empty (idempotent fast path: if the panel already loaded metadata, the form fills synchronously with no flicker; if not, it waits for the IPC before populating the dropdowns).
• Call sites (edit button, add button) wrap the fire-and-forget promise with .catch(() => {}) for safety.

Test (emrg/gui/test/renderer.smoke.test.js):

• New regression test with 50ms-delayed taskTemplateList/listProjects mocks: open the panel, immediately click "＋ Add Task", assert both dropdowns end up populated and a quick save submits a taskCreate payload with non-empty type/project.

Verification: GUI 245 → 246 all green (new test passes; existing P3 task-form tests unchanged), node --check clean, pytest 805 unchanged (doc-count guard synced in Agent.md).

[argszero]

✅ LGTM — cycle

[argszero]

✅ LGTM — cycle

[argszero]

✅ LGTM — cycle

[argszero]

✅ LGTM — cycle