fix(sample-app): address PR #18 review findings (#19)

- WebLedgerStore.accountExistsByName case-insensitive (matches SQL COLLATE NOCASE)
- drop SampleApplication.maybeInjectDebugError; sample spec now passes clean
- drop noLogcatErrors from sample spec (default matches system-wide E logs)
- openRandomAccount picks uniformly from findAll instead of first match
- clear txnError on any add-transaction interaction, not only valid amount input
- escapeForAdbInputText quotes shell metacharacters (quotes, backslash, etc.)
- extract buildClearKeyevents helper with empty/normal/cap tests
- broaden spec_integration_test.go to cover home, add-account, ledger,
  add-transaction action generators
- document FocusTracker single-focus invariant

examples/sample-app/composeApp/src/androidMain/kotlin/dev/uatu/sample/SampleApplication.kt

@@ -1,7 +1,6 @@
 package dev.uatu.sample
 
 import android.app.Application
-import android.content.pm.ApplicationInfo
 import dev.uatu.sdk.Uatu
 
 class SampleApplication : Application() {
@@ -80,16 +79,5 @@ class SampleApplication : Application() {
         Uatu.extract("login_error") { UiState.loginError.value }
         Uatu.extract("add_account_error") { UiState.addAccountError.value }
         Uatu.extract("txn_error") { UiState.txnError.value }
-        maybeInjectDebugError()
-    }
-
-    // Fires a synthetic Uatu.reportError in debug builds so the sample-app
-    // e2e run can verify noUncaughtExceptions surfaces SDK-captured errors
-    // in the trace. Production builds skip this.
-    private fun maybeInjectDebugError() {
-        val isDebuggable = applicationInfo.flags and ApplicationInfo.FLAG_DEBUGGABLE != 0
-        if (isDebuggable) {
-            Uatu.reportError(RuntimeException("synthetic"))
-        }
     }
 }

examples/sample-app/composeApp/src/commonMain/kotlin/dev/uatu/sample/FocusTracker.kt

@@ -4,6 +4,9 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
 import kotlinx.coroutines.flow.asStateFlow
 
+// Assumes single-focus: only one input can be focused at a time, so
+// enter() overwriting is safe. leave() is id-gated so a stale dispose
+// from a previously-focused field cannot clobber the active focus.
 object FocusTracker {
     private val _current = MutableStateFlow<String?>(null)
     val current: StateFlow<String?> = _current.asStateFlow()

examples/sample-app/composeApp/src/commonMain/kotlin/dev/uatu/sample/ui/AddTransaction.kt

@@ -103,7 +103,10 @@ fun AddTransactionPage(accountId: String) {
             Segmented(
                 selected = if (type == TxnType.credit) 0 else 1,
                 labels = listOf("Credit", "Debit"),
-                onSelect = { type = if (it == 0) TxnType.credit else TxnType.debit },
+                onSelect = {
+                    UiState.txnError.value = ""
+                    type = if (it == 0) TxnType.credit else TxnType.debit
+                },
                 descriptions = listOf("txn_credit", "txn_debit"),
             )
             Column(verticalArrangement = Arrangement.spacedBy(6.dp)) {
@@ -111,9 +114,9 @@ fun AddTransactionPage(accountId: String) {
                 TextInput(
                     value = amount,
                     onChange = {
+                        UiState.txnError.value = ""
                         if (AMOUNT_REGEX.matches(it) || it.isEmpty()) {
                             amount = it
-                            UiState.txnError.value = ""
                         }
                     },
                     placeholder = "0.00",
@@ -129,7 +132,10 @@ fun AddTransactionPage(accountId: String) {
                 FieldLabel("Note (optional)")
                 TextInput(
                     value = note,
-                    onChange = { note = it.take(80) },
+                    onChange = {
+                        UiState.txnError.value = ""
+                        note = it.take(80)
+                    },
                     placeholder = "What's this for?",
                     label = "Note",
                     description = "txn_note",

examples/sample-app/composeApp/src/wasmJsMain/kotlin/dev/uatu/sample/WebLedgerStore.kt

@@ -21,7 +21,7 @@ class WebLedgerStore : LedgerStore {
     }
 
     override fun accountExistsByName(name: String): Boolean =
-        _accounts.value.any { it.name == name }
+        _accounts.value.any { it.name.equals(name, ignoreCase = true) }
 
     override fun insertAccount(id: String, name: String, createdAt: Long) {
         _accounts.value = _accounts.value + Account(id, name, createdAt)