Refactor authentication architecture to eliminate dual auth complexity

This major refactor consolidates the authentication system to use a single
source of truth, eliminating timing issues and architectural complexity
that was causing chat and payment functionality problems.

Key Changes:
• Remove old global useAuth composable and replace with useAuthService wrapper
• Update all 25+ files to use consistent auth pattern via dependency injection
• Eliminate dual auth detection workarounds from services (ChatService, PaymentService, etc.)
• Fix TypeScript errors and add proper Uint8Array conversion for Nostr private keys
• Consolidate auth state management to AuthService as single source of truth

Benefits:
• Resolves chat peer loading and message subscription timing issues
• Fixes wallet detection problems for Lightning payments
• Eliminates race conditions between global and injected auth
• Maintains API compatibility while improving architecture
• Reduces code complexity and improves maintainability

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

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

src/modules/base/auth/auth-service.ts

@@ -1,8 +1,8 @@
 // Auth service for LNbits integration
-import { ref } from 'vue'
+import { ref, computed } from 'vue'
 import { BaseService } from '@/core/base/BaseService'
 import { eventBus } from '@/core/event-bus'
-import { lnbitsAPI, type LoginCredentials, type RegisterData } from '@/lib/api/lnbits'
+import { lnbitsAPI, type LoginCredentials, type RegisterData, type User } from '@/lib/api/lnbits'
 
 export class AuthService extends BaseService {
   // Service metadata
@@ -14,8 +14,23 @@ export class AuthService extends BaseService {
 
   // Public state
   public isAuthenticated = ref(false)
-  public user = ref<any>(null)
+  public user = ref<User | null>(null)
   public isLoading = ref(false)
+  public error = ref<Error | null>(null)
+  
+  // Computed properties for compatibility with global auth
+  public currentUser = computed(() => this.user.value)
+  public userDisplay = computed(() => {
+    if (!this.user.value) return null
+    
+    return {
+      name: this.user.value.username || this.user.value.email || 'Anonymous',
+      username: this.user.value.username,
+      email: this.user.value.email,
+      id: this.user.value.id,
+      shortId: this.user.value.id.slice(0, 8) + '...' + this.user.value.id.slice(-8)
+    }
+  })
 
   /**
    * Service-specific initialization (called by BaseService)
@@ -104,10 +119,11 @@ export class AuthService extends BaseService {
     }
   }
 
-  logout(): void {
+  async logout(): Promise<void> {
     lnbitsAPI.logout()
     this.user.value = null
     this.isAuthenticated.value = false
+    this.error.value = null
     
     eventBus.emit('auth:logout', {}, 'auth-service')
   }
@@ -116,6 +132,37 @@ export class AuthService extends BaseService {
     // Re-fetch user data from API
     await this.checkAuth()
   }
+  
+  async initialize(): Promise<void> {
+    // Alias for checkAuth for compatibility
+    await this.checkAuth()
+  }
+  
+  async updatePassword(currentPassword: string, newPassword: string): Promise<void> {
+    try {
+      this.isLoading.value = true
+      const updatedUser = await lnbitsAPI.updatePassword(currentPassword, newPassword)
+      this.user.value = updatedUser
+    } catch (error) {
+      const err = this.handleError(error, 'updatePassword')
+      throw err
+    } finally {
+      this.isLoading.value = false
+    }
+  }
+  
+  async updateProfile(data: Partial<User>): Promise<void> {
+    try {
+      this.isLoading.value = true
+      const updatedUser = await lnbitsAPI.updateProfile(data)
+      this.user.value = updatedUser
+    } catch (error) {
+      const err = this.handleError(error, 'updateProfile')
+      throw err
+    } finally {
+      this.isLoading.value = false
+    }
+  }
 
   /**
    * Cleanup when service is disposed