fix: convert Map to Record for server-client boundary, remove dead currentUser prop

- WeatherBoard: change previousEntries type from Map<string, PreviousEntry> to Record<string, PreviousEntry> and update lookup from .get() to bracket notation
- page.tsx: wrap previousEntries with Object.fromEntries() before passing as prop, remove unused currentUser prop
- WeatherCard: remove spurious eslint-disable-next-line comment for non-existent rule react-hooks/set-state-in-effect

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/weather/[id]/page.tsx

@@ -93,11 +93,6 @@ export default async function WeatherSessionPage({ params }: WeatherSessionPageP
         <WeatherBoard
           sessionId={session.id}
           currentUserId={authSession.user.id}
-          currentUser={{
-            id: authSession.user.id,
-            name: authSession.user.name ?? null,
-            email: authSession.user.email ?? '',
-          }}
           entries={session.entries}
           shares={session.shares}
           owner={{
@@ -106,7 +101,7 @@ export default async function WeatherSessionPage({ params }: WeatherSessionPageP
             email: session.user.email ?? '',
           }}
           canEdit={session.canEdit}
-          previousEntries={previousEntries}
+          previousEntries={Object.fromEntries(previousEntries)}
         />
       </WeatherLiveWrapper>
     </main>