Fix TOTP code freeze when adding new items in Authenticator

Use SharingStarted.Eagerly for per-item StateFlows to prevent them from
stopping emissions when the combined flow changes. This fixes an issue
where adding a new TOTP code would cause existing codes to freeze
permanently because WhileSubscribed() with no timeout immediately stops
flows when subscribers change.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: tajchert

authenticator/src/main/kotlin/com/bitwarden/authenticator/data/authenticator/manager/TotpCodeManagerImpl.kt

@@ -83,7 +83,7 @@ class TotpCodeManagerImpl @Inject constructor(
                 }
                 .stateIn(
                     scope = itemScope,
-                    started = SharingStarted.WhileSubscribed(),
+                    started = SharingStarted.Eagerly,
                     initialValue = null,
                 )
         }