feat(sessions): keyboard navigation and jump-to-message picker

[charlesvien]

Recreates #2361, which GitHub refuses to reopen because the head branch was force-pushed after it was closed. Same branch and author (@Basit-Balogun10), now including the two commits that port the feature onto the new ChatThread (8ff1896, f733e63).

Note: still stacked on #2321, so the diff includes its 21 commits (cross-fork branches can't be PR bases). The actual change here is the last two commits.

Adds Alt/Option+Up/Down navigation between user messages, a Cmd/Ctrl+J jump-to-message picker with date filtering and the matching entries in the shortcuts sheet. See #2361 for the full description and demo videos.

Closes #2360.

[trunk-io]

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[greptile-apps]

_{Reviews (1): Last reviewed commit: "fix(sessions): ChatThread focus ring + j..." | Re-trigger Greptile}

[greptile-apps]

Added Binding Replaces Defaults

When a shortcut is still using defaults, “Add another binding” saves only the new combo because addKeybinding starts from an empty custom array. A user adding a second binding for New task loses mod+n and mod+t, so the advertised defaults stop working after the first customization.

Suggested change

	const handleSave = useCallback(
	(combo: string) => {
	if (recordingMode?.type === "edit") {
	updateKeybinding(id, recordingMode.key, combo);
	} else {
	addKeybinding(id, combo);
	}
	stopRecording();
	},
	[recordingMode, id, updateKeybinding, addKeybinding, stopRecording],
	);
	const handleSave = useCallback(
	(combo: string) => {
	if (recordingMode?.type === "edit") {
	updateKeybinding(id, recordingMode.key, combo);
	} else {
	if (!hasCustom) {
	for (const key of defaultBindings) {
	addKeybinding(id, key);
	}
	}
	addKeybinding(id, combo);
	}
	stopRecording();
	},
	[
	recordingMode,
	id,
	updateKeybinding,
	addKeybinding,
	stopRecording,
	hasCustom,
	defaultBindings,
	],
	);

[greptile-apps]

End Minute Excludes Messages

The custom to filter compares messages against the exact start of the selected minute. If a user chooses 14:30 as the end time, messages sent at 14:30:01 through 14:30:59 are hidden from the picker, so they cannot be selected even though they fall within the chosen minute.

Suggested change

	if (customTo) {
	filtered = filtered.filter(
	(e) => e.timestamp <= new Date(customTo).getTime(),
	);
	}
	if (customTo) {
	const to = new Date(customTo);
	to.setSeconds(59, 999);
	filtered = filtered.filter((e) => e.timestamp <= to.getTime());
	}

[charlesvien]

Superseded by #3407, same work squashed into a single commit and rebased onto main.