fix: prevent staking dashboard hang when exposure flag not cached

isPagedExposuresUsed() called storageCache.getEntry() which suspends
forever if the entry doesn't exist. The flag is only written by
ValidatorExposureUpdater (staking detail flow), so the dashboard
would hang indefinitely waiting for it.

Check cache first with isFullKeyInCache() and default to paged
exposures when the flag is absent. Also remove debug log statements.

common/src/main/java/io/novafoundation/nova/common/data/memory/RealComputationalCache.kt

@@ -1,7 +1,5 @@
 package io.novafoundation.nova.common.data.memory
 
-import android.util.Log
-import io.novafoundation.nova.common.utils.LOG_TAG
 import io.novafoundation.nova.common.utils.flowOfAll
 import io.novafoundation.nova.common.utils.inBackground
 import io.novafoundation.nova.common.utils.invokeOnCompletion
@@ -75,17 +73,12 @@ internal class RealComputationalCache : ComputationalCache, CoroutineScope by Co
         val awaitable = mutex.withLock {
             val existing = memory[key]
             if (existing != null && existing.aggregateScope.isActive) {
-                Log.d(LOG_TAG, "Key $key requested - already present")
-
                 existing.dependents += scope
 
                 existing.awaitable
             } else {
                 if (existing != null) {
-                    Log.d(LOG_TAG, "Key $key requested - stale (aggregateScope cancelled), recreating")
                     memory.remove(key)
-                } else {
-                    Log.d(LOG_TAG, "Key $key requested - creating new operation")
                 }
 
                 val aggregateScope = CoroutineScope(Dispatchers.Default)
@@ -104,13 +97,9 @@ internal class RealComputationalCache : ComputationalCache, CoroutineScope by Co
                         entry.dependents -= scope
 
                         if (entry.dependents.isEmpty()) {
-                            Log.d(this@RealComputationalCache.LOG_TAG, "Key $key - last scope cancelled")
-
                             memory.remove(key)
 
                             entry.aggregateScope.cancel()
-                        } else {
-                            Log.d(this@RealComputationalCache.LOG_TAG, "Key $key - scope cancelled, ${entry.dependents.size} remaining")
                         }
                     }
                 }