fix(ui): resolve editor race condition and default personality inheritance

**Problem:**
1. Personality/SystemPrompt editors showed empty fields on first open (race condition)
2. Changing default personality in preferences didn't affect new conversations
3. Mermaid diagrams render poorly for complex flows (hardcoded spacing)

**Solution:**
1. Replaced .onAppear pattern with custom init() in editors:
   - PersonalityEditor: Initialize @State values directly from personality parameter
   - SystemPromptConfigurationEditor: Same pattern for consistency
   - Data available immediately when view appears, no async delay

2. ConversationSettings.init() now reads defaultPersonalityId from UserDefaults:
   - Falls back to Assistant UUID if not set
   - New conversations inherit user's default personality preference

3. Issue #3 investigated but not fixed in this commit:
   - All Mermaid renderers use hardcoded sizing (nodeWidth=180, spacing=100, etc.)
   - Recommendation: Switch to mermaid   - Recommendation: Switch to mermaid   - Recommendation: Switch to mermaid   - Recommendation: Switchg:*   - Recomm:    - Recommendation: Switch to mermaid   - Recommendation: Switch to mermaide view displays
✅ Default personality now inherited by new conversations

Author: fewtarius

Sources/ConversationEngine/ConversationModel.swift

@@ -148,7 +148,22 @@ public struct ConversationSettings: Codable, Sendable {
         self.maxTokens = maxTokens
         self.contextWindowSize = contextWindowSize
         self.workspacePromptIds = workspacePromptIds
-        self.selectedPersonalityId = selectedPersonalityId
+        
+        /// Default to user's selected default personality if none specified
+        /// This ensures new conversations inherit the personality preference
+        if let providedPersonalityId = selectedPersonalityId {
+            self.selectedPersonalityId = providedPersonalityId
+        } else {
+            // Get default personality from PersonalityManager
+            // This is synchronous and safe as PersonalityManager is @MainActor
+            if let defaultId = UUID(uuidString: UserDefaults.standard.string(forKey: "defaultPersonalityId") ?? "") {
+                self.selectedPersonalityId = defaultId
+            } else {
+                // Fallback to Assistant (first default personality)
+                self.selectedPersonalityId = UUID(uuidString: "00000000-0000-0000-0000-000000000001")
+            }
+        }
+        
         self.enableReasoning = enableReasoning
         self.enableTools = enableTools
         self.autoApprove = autoApprove

Sources/UserInterface/PersonalityManagementView.swift

@@ -122,10 +122,30 @@ struct PersonalityEditor: View {
     let personalityManager: PersonalityManager
     @Binding var isPresented: Bool
 
-    @State private var name: String = ""
-    @State private var description: String = ""
-    @State private var selectedTraits: [PersonalityTraitCategory: PersonalityTrait] = [:]
-    @State private var customInstructions: String = ""
+    @State private var name: String
+    @State private var description: String
+    @State private var selectedTraits: [PersonalityTraitCategory: PersonalityTrait]
+    @State private var customInstructions: String
+
+    /// Initialize with data immediately - no .onAppear race condition
+    init(personality: Personality?, personalityManager: PersonalityManager, isPresented: Binding<Bool>) {
+        self.personality = personality
+        self.personalityManager = personalityManager
+        self._isPresented = isPresented
+        
+        // Initialize State values directly from personality (if editing) or defaults (if new)
+        if let personality = personality {
+            self._name = State(initialValue: personality.name)
+            self._description = State(initialValue: personality.description)
+            self._selectedTraits = State(initialValue: personality.selectedTraits)
+            self._customInstructions = State(initialValue: personality.customInstructions)
+        } else {
+            self._name = State(initialValue: "")
+            self._description = State(initialValue: "")
+            self._selectedTraits = State(initialValue: [:])
+            self._customInstructions = State(initialValue: "")
+        }
+    }
 
     private var isEditing: Bool { personality != nil }
     private var title: String { isEditing ? "Edit Personality" : "New Personality" }
@@ -297,18 +317,6 @@ struct PersonalityEditor: View {
         }
         .frame(minWidth: 600, idealWidth: 800, maxWidth: 1000,
                minHeight: 500, idealHeight: 700, maxHeight: .infinity)
-        .onAppear {
-            setupInitialValues()
-        }
-    }
-
-    private func setupInitialValues() {
-        if let personality = personality {
-            name = personality.name
-            description = personality.description
-            selectedTraits = personality.selectedTraits
-            customInstructions = personality.customInstructions
-        }
     }
 
     private func savePersonality() {

Sources/UserInterface/SystemPromptManagementView.swift

@@ -91,13 +91,31 @@ struct SystemPromptConfigurationEditor: View {
     let promptManager: SystemPromptManager
     @Binding var isPresented: Bool
 
-    @State private var name: String = ""
-    @State private var description: String = ""
-    @State private var components: [SystemPromptComponent] = []
+    @State private var name: String
+    @State private var description: String
+    @State private var components: [SystemPromptComponent]
     @State private var showingNewComponent = false
     @State private var showingComponentLibrary = false
     @State private var editingComponent: SystemPromptComponent?
 
+    /// Initialize with data immediately - no .onAppear race condition
+    init(configuration: SystemPromptConfiguration?, promptManager: SystemPromptManager, isPresented: Binding<Bool>) {
+        self.configuration = configuration
+        self.promptManager = promptManager
+        self._isPresented = isPresented
+        
+        // Initialize State values directly from configuration (if editing) or defaults (if new)
+        if let configuration = configuration {
+            self._name = State(initialValue: configuration.name)
+            self._description = State(initialValue: configuration.description)
+            self._components = State(initialValue: configuration.components)
+        } else {
+            self._name = State(initialValue: "")
+            self._description = State(initialValue: "")
+            self._components = State(initialValue: [])
+        }
+    }
+
     private var isEditing: Bool { configuration != nil }
     private var title: String { isEditing ? "Edit Template" : "New Template" }
 
@@ -230,9 +248,6 @@ struct SystemPromptConfigurationEditor: View {
         }
         .frame(minWidth: 600, idealWidth: 800, maxWidth: 1000,
                minHeight: 500, idealHeight: 700, maxHeight: .infinity)
-        .onAppear {
-            setupInitialValues()
-        }
         .sheet(isPresented: $showingNewComponent) {
             SystemPromptComponentEditor(
                 component: nil,
@@ -270,14 +285,6 @@ struct SystemPromptConfigurationEditor: View {
         }
     }
 
-    private func setupInitialValues() {
-        if let configuration = configuration {
-            name = configuration.name
-            description = configuration.description
-            components = configuration.components
-        }
-    }
-
     private func generatePreviewPrompt() -> String {
         return components
             .filter { $0.isEnabled }