Social sign-in, new conversations, and a complete users page

Google and Apple sign-in, agent-initiated conversations, spam management, and a full users page.

• Sign in with Google or Apple on web and iOS, auto-links existing accounts
• Compose button to start conversations with any customer by email
• Mark conversations as spam from the right-click menu, AI assistant skips spam automatically
• Pin conversations to the top of the inbox
• Filter by "Your inbox" or "Unassigned"
• Search within a conversation thread, navigate matches with Enter and Shift+Enter
• System messages for resolved, reopened, and reassigned events
• Users page: search, sort, filter by All/Starred/Blocked
• Password reset from login page
• Green online indicators for team members
• Helpdock to SupportWire rebrand complete across all platforms