tui: remove unused imports and variables from header component to clean up code

packages/opencode/src/cli/cmd/tui/routes/session/header.tsx

@@ -3,9 +3,8 @@ import { useRouteData } from "@tui/context/route"
 import { useSync } from "@tui/context/sync"
 import { pipe, sumBy } from "remeda"
 import { useTheme } from "@tui/context/theme"
-import { SplitBorder, EmptyBorder } from "@tui/component/border"
+import { SplitBorder } from "@tui/component/border"
 import type { AssistantMessage, Session } from "@opencode-ai/sdk/v2"
-import { useDirectory } from "../../context/directory"
 import { useKeybind } from "../../context/keybind"
 
 const Title = (props: { session: Accessor<Session> }) => {
@@ -33,7 +32,6 @@ export function Header() {
   const sync = useSync()
   const session = createMemo(() => sync.session.get(route.sessionID)!)
   const messages = createMemo(() => sync.data.message[route.sessionID] ?? [])
-  const shareEnabled = createMemo(() => sync.data.config.share !== "disabled")
 
   const cost = createMemo(() => {
     const total = pipe(