0.2.36: Investor View carries exit status + grey out fully-exited fund cards

The admin read-only Investor View built capital-account responses
without exited_on, so an exited position showed the active card with
$0s (the LP's own portal was correct). Extracted exit_dates() into
capital_account_router and stamp it in investor_view too; regression
test added. A fund card where every position is exited now renders
greyed (bg + title) so it reads as closed at a glance.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

frontend/src/version.ts

@@ -1,4 +1,4 @@
 // Bumped each release so the running build is visible in the UI.
 // If the number shown in the app doesn't match the installed s9pk version,
 // the new frontend isn't actually being served.
-export const APP_VERSION = "0.2.35";
+export const APP_VERSION = "0.2.36";