Name the default fork destination in tab menus

Merged
LA
4mo ago
+84-41

The primary tab context-menu action now names its configured destination, such as “Fork Conversation to the Right”. The existing destination submenu remains available.

Tests: swift test --filter 'BonsplitTests.testTabContextMenuBuilderCreatesForkConversationSubmenu|BonsplitTests.testTabContextMenuBuilderKeepsForkConversationVisibleWhenOpenAvailabilityIsRefreshing'

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Summary by cubic

Show the configured default fork destination in the tab context menu’s primary action (e.g., “Fork Conversation to the Right”). Replace the fork availability APIs with a hidden/refreshing/available state so the item can stay visible but disabled while loading; submenu unchanged and en/ja labels added.