opencode attach crashes with 'session().parentID' error in v1.1.1 (regression from #6319) #6874

Description

After upgrading from v1.0.223 to v1.1.1, the opencode attach command crashes immediately when trying to attach to a session.

Error

TypeError: undefined is not an object (evaluating 'session().parentID')
    at <anonymous> (src/cli/cmd/tui/routes/session/index.tsx:82:17)
    at runComputation (../../node_modules/.bun/solid-js@1.9.10/node_modules/solid-js/dist/dev.js:742:22)
    at updateComputation (../../node_modules/.bun/solid-js@1.9.10/node_modules/solid-js/dist/dev.js:724:3)
    at createMemo (../../node_modules/.bun/solid-js@1.9.10/node_modules/solid-js/dist/dev.js:273:10)
    at Session4 (src/cli/cmd/tui/routes/session/index.tsx:81:23)
    ...

Root Cause

Introduced in commit 351ddeed9 ("Permission rework #6319"). The permissions memo accesses session().parentID without optional chaining, but session() can be undefined when the session data hasn't loaded yet (e.g., during attach):

// packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
const permissions = createMemo(() => {
  if (session().parentID) return sync.data.permission[route.sessionID] ?? []
  //     ^^^^^^^^^ Missing optional chaining
  return children().flatMap((x) => sync.data.permission[x.id] ?? [])
})

The children memo on line ~108 correctly uses session()?.parentID, but the permissions memo on line ~119 doesn't.

Suggested Fix

- if (session().parentID) return sync.data.permission[route.sessionID] ?? []
+ if (session()?.parentID) return sync.data.permission[route.sessionID] ?? []

Steps to Reproduce

1. Start an OpenCode server: opencode serve or opencode web
2. Create a session
3. From another terminal: opencode attach http://localhost:<port> --session <id>
4. Error appears immediately

Versions

Workaround

opencode upgrade 1.0.223