feat(desktop): add home session actions - #43245

AI code review — automated review for reference; please use your judgment.

• packages/app/src/pages/home/home-sessions-controller.tsx:228-231 — DeleteDialog's confirm has no in-flight guard, so a double-click on "Delete session" fires two DELETE requests; the second rejects once the session is gone and pops an error toast after the dialog already closed. Track a pending state and disable the danger button until remove() settles.
• packages/app/src/pages/home/home-sessions-view.tsx:513 — the rename input's onKeyDown calls event.stopPropagation() for every key, not just Enter/Escape, which blocks all global keybinds (command palette, search, tab switching) while the editor is open. Stop propagation only for the keys you actually handle.
• packages/app/src/pages/home/home-sessions-controller.tsx:51 and :82 — removed.keys grows without bound and is scanned with Array.includes() inside the indexedSessions memo, making every recompute O(sessions × removed) on a long-lived home page. Use a Set (or a record keyed by `${server}\0${id}`) instead of an array scan.
• packages/app/src/pages/home/home-sessions-controller.tsx:151 — rename() returns true for a blank title, so committing an empty field exits through the "saved" path and callers can't distinguish saved from cancelled. Return false (or a tri-state) for the blank case so saveEditor's saved flag keeps its meaning.
• packages/app/src/pages/home/home-sessions-view.tsx:445-451 — finishLongPress resets suppressClick in an untracked setTimeout, relying on task ordering between that timer and the browser-synthesized click; a delayed click or a second long-press in the same tick can clear the flag at the wrong moment and let the tap fall through to onOpenSession. Track the reset timer like longPressTimer, or consume the flag synchronously in onClick.
• packages/app/src/pages/home/home-sessions-view.tsx:501-524 (nit) — the rename InlineInput has no accessible label, so screen readers announce an unlabeled edit field; an aria-label from the existing rename strings would fix it.