Add centralized DateUtils and enhance contractor detail views

- Add DateUtils.kt for shared Kotlin date formatting with formatDate,
  formatDateMedium, formatDateTime, formatRelativeDate, and isOverdue
- Add DateUtils.swift for iOS with matching date formatting functions
- Enhance ContractorDetailScreen (Android) with quick action buttons
  (call, email, website, directions), clickable contact rows, residence
  association, statistics section, and metadata
- Enhance ContractorDetailView (iOS) with same features, refactored into
  smaller @ViewBuilder functions to fix Swift compiler type-check timeout
- Fix empty string handling in iOS - check !isEmpty in addition to != nil
  for optional fields like phone, email, website, address
- Update various task and document views to use centralized DateUtils

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

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

composeApp/src/commonMain/kotlin/com/example/casera/ui/components/task/CompletionHistorySheet.kt

@@ -16,6 +16,7 @@ import com.example.casera.models.TaskCompletionResponse
 import com.example.casera.models.TaskCompletion
 import com.example.casera.network.ApiResult
 import com.example.casera.network.APILayer
+import com.example.casera.util.DateUtils
 import kotlinx.coroutines.launch
 
 /**
@@ -259,7 +260,7 @@ private fun CompletionHistoryCard(completion: TaskCompletionResponse) {
             ) {
                 Column {
                     Text(
-                        text = formatCompletionDate(completion.completedAt),
+                        text = DateUtils.formatDateMedium(completion.completedAt),
                         style = MaterialTheme.typography.titleMedium,
                         fontWeight = FontWeight.Bold,
                         color = MaterialTheme.colorScheme.onSurface
@@ -377,26 +378,3 @@ private fun CompletionHistoryCard(completion: TaskCompletionResponse) {
         )
     }
 }
-
-private fun formatCompletionDate(dateString: String): String {
-    // Try to parse and format the date
-    return try {
-        val parts = dateString.split("T")
-        if (parts.isNotEmpty()) {
-            val dateParts = parts[0].split("-")
-            if (dateParts.size == 3) {
-                val year = dateParts[0]
-                val month = dateParts[1].toIntOrNull() ?: 1
-                val day = dateParts[2].toIntOrNull() ?: 1
-                val monthNames = listOf("", "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec")
-                "${monthNames.getOrElse(month) { "Jan" }} $day, $year"
-            } else {
-                dateString
-            }
-        } else {
-            dateString
-        }
-    } catch (e: Exception) {
-        dateString
-    }
-}

composeApp/src/commonMain/kotlin/com/example/casera/ui/components/task/SimpleTaskListItem.kt

@@ -7,6 +7,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
+import com.example.casera.util.DateUtils
 import org.jetbrains.compose.ui.tooling.preview.Preview
 
 @Composable
@@ -77,7 +78,7 @@ fun SimpleTaskListItem(
                 )
                 if (dueDate != null) {
                     Text(
-                        text = "Due: $dueDate",
+                        text = "Due: ${DateUtils.formatDate(dueDate)}",
                         style = MaterialTheme.typography.bodySmall,
                         color = if (isOverdue)
                             MaterialTheme.colorScheme.error

composeApp/src/commonMain/kotlin/com/example/casera/ui/components/task/TaskCard.kt

@@ -20,6 +20,7 @@ import com.example.casera.models.TaskPriority
 import com.example.casera.models.TaskFrequency
 import com.example.casera.models.TaskStatus
 import com.example.casera.models.TaskCompletion
+import com.example.casera.util.DateUtils
 import org.jetbrains.compose.ui.tooling.preview.Preview
 
 @Composable
@@ -167,7 +168,7 @@ fun TaskCard(
                         tint = MaterialTheme.colorScheme.onSurfaceVariant
                     )
                     Text(
-                        text = task.nextScheduledDate ?: task.dueDate ?: "N/A",
+                        text = DateUtils.formatDate(task.nextScheduledDate ?: task.dueDate) ?: "N/A",
                         style = MaterialTheme.typography.labelSmall,
                         color = MaterialTheme.colorScheme.onSurfaceVariant
                     )