Android overhaul: shared failure texts, saved-split label and limits in :core:design

* format/Failures.kt: FAILURE_NETWORK and commonFailureText, the §14.3.2 code-to-text map that :feature:account
  (Errors.kt) and :feature:settings (Messages.kt) each spelled out; both keep only their own codes. The "network"
  literals in :feature:onboarding and the two NETWORK constants use FAILURE_NETWORK.
* component/Split.kt: savedSplitLabel, the S-8 and S-16 line ("Kontots standard 50/50", "Egen fördelning 70/30",
  "Exakta belopp", "Allt på dig/Anna") that ExpenseDetailScreen.modeLabel and SyncStatusScreen.lostModeLabel
  duplicated line for line.
* format/Limits.kt: BP_TOTAL (five copies in four features and a literal in :core:design and S-19) and
  DISPLAY_NAME_MAX (three copies in :feature:onboarding and :feature:settings).

Behaviour and goldens unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TQd3pEP9UeN2uifbHknQ7B

android/feature/account/src/main/kotlin/se/hagstedt/kvitt/feature/account/AccountDetailScreen.kt

@@ -45,6 +45,7 @@ import se.hagstedt.kvitt.design.component.TopBarNavigation
 import se.hagstedt.kvitt.design.component.kvittLanguage
 import se.hagstedt.kvitt.design.component.ratioSpoken
 import se.hagstedt.kvitt.design.component.showKvittSnackbar
+import se.hagstedt.kvitt.design.format.BP_TOTAL
 import se.hagstedt.kvitt.design.format.MoneyFormatter
 import se.hagstedt.kvitt.design.icon.KvittIcon
 import se.hagstedt.kvitt.model.AccountId
@@ -215,7 +216,6 @@ private fun defaultSplit(ui: AccountDetailUi.Ready): String {
     return stringResource(R.string.account_default_split, ratio, names)
 }
 
-internal const val BP_TOTAL = 10_000
 
 /** `more_vert` with the S-5 menu; disabled items carry their reason as a second line (design-spec §3.11). */
 @Composable

android/feature/account/src/main/kotlin/se/hagstedt/kvitt/feature/account/AccountDetailViewModel.kt

@@ -11,6 +11,7 @@ import kotlinx.coroutines.flow.combine
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
+import se.hagstedt.kvitt.design.format.FAILURE_NETWORK
 import se.hagstedt.kvitt.model.AccountDetailState
 import se.hagstedt.kvitt.model.AccountId
 import se.hagstedt.kvitt.model.AccountRepository
@@ -170,10 +171,7 @@ class AccountDetailViewModel @Inject constructor(
 }
 
 private fun failureMessage(code: String, action: AccountAction): AccountMessage = when (code) {
-    NETWORK -> AccountMessage.CouldNotReach(action)
+    FAILURE_NETWORK -> AccountMessage.CouldNotReach(action)
     "account_not_empty" -> AccountMessage.DeleteBlocked
     else -> AccountMessage.Failed(code)
 }
-
-/** `OnlineResult.Failed` code of a network failure (design-spec §1, §9.9). */
-internal const val NETWORK = "network"

android/feature/account/src/main/kotlin/se/hagstedt/kvitt/feature/account/AccountEditorScreen.kt

@@ -54,6 +54,7 @@ import se.hagstedt.kvitt.design.component.kvittLanguage
 import se.hagstedt.kvitt.design.component.money
 import se.hagstedt.kvitt.design.component.ratioSpoken
 import se.hagstedt.kvitt.design.component.showKvittSnackbar
+import se.hagstedt.kvitt.design.format.BP_TOTAL
 import se.hagstedt.kvitt.design.format.MoneyFormatter
 import se.hagstedt.kvitt.design.icon.KvittIcon
 import se.hagstedt.kvitt.design.theme.KvittDimens

android/feature/account/src/main/kotlin/se/hagstedt/kvitt/feature/account/AccountEditorViewModel.kt

@@ -13,6 +13,8 @@ import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.flow.stateIn
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
+import se.hagstedt.kvitt.design.format.BP_TOTAL
+import se.hagstedt.kvitt.design.format.FAILURE_NETWORK
 import se.hagstedt.kvitt.model.AccountId
 import se.hagstedt.kvitt.model.AccountRepository
 import se.hagstedt.kvitt.model.ConnectivityRepository
@@ -183,7 +185,7 @@ private fun AccountEditorUi.failed(code: String, field: String?): AccountEditorU
     code == "name_taken" -> copy(saving = false, serverNameError = NameError.Taken(name.trim()))
     code == "validation_failed" && field == "name" -> copy(saving = false, serverNameError = NameError.Invalid)
     code == "validation_failed" && field == "default_shares" -> copy(saving = false, splitError = true)
-    code == NETWORK -> copy(saving = false, message = EditorMessage.CouldNotReach)
+    code == FAILURE_NETWORK -> copy(saving = false, message = EditorMessage.CouldNotReach)
     else -> copy(saving = false, message = EditorMessage.Failed(code))
 }
 

android/feature/account/src/main/kotlin/se/hagstedt/kvitt/feature/account/Errors.kt

@@ -1,19 +1,12 @@
 package se.hagstedt.kvitt.feature.account
 
 import androidx.annotation.StringRes
+import se.hagstedt.kvitt.design.format.commonFailureText
 import se.hagstedt.kvitt.core.design.R as DesignR
 
 /** The snackbar text of an `OnlineResult.Failed` code without a field at fault (§14.3.2, strings.csv `error_*`). */
 @StringRes
 internal fun errorText(code: String): Int = when (code) {
-    NETWORK -> DesignR.string.common_could_not_reach_server
-    "household_incomplete" -> DesignR.string.error_household_incomplete
-    "not_found" -> DesignR.string.error_not_found
-    "forbidden" -> DesignR.string.error_forbidden
-    "rate_limited" -> DesignR.string.error_rate_limited
-    "protocol_unsupported" -> DesignR.string.error_app_too_old
-    "internal", "unavailable", "not_implemented" -> DesignR.string.error_server
-    "validation_failed" -> DesignR.string.error_validation
     "account_not_empty" -> R.string.account_delete_blocked
-    else -> DesignR.string.error_generic_invalid
+    else -> commonFailureText(code) ?: DesignR.string.error_generic_invalid
 }