feat: implement user profiles and settings

Add comprehensive user profile system allowing users to showcase
their activity and customize their profiles.

Database Changes:
- Added profile fields to User model: slug, displayName, bio, profilePublic
- Added index on slug field for efficient lookups

API Changes:
- Added GET /users/me endpoint to fetch current user
- Added PUT /users/me endpoint to update user settings
- Added GET /users/profile/:identifier endpoint for public profiles
- Updated UserService with profile methods and statistics
- Modified AuthService to include profile fields in user responses

Frontend Changes:
- Created ProfileComponent to display user profiles with stats
- Created SettingsComponent for profile customization
- Added profile and settings routes
- Updated header dropdown menu with profile links
- Enhanced UserService with profile methods
- Added updateUser method to AuthService

Features:
- Custom profile slugs for clean URLs
- Display names separate from usernames
- User bios (up to 500 characters)
- Public/private profile toggle
- Activity statistics (suggestions, likes, comments, acceptance rate)
- Badge display (Staff, Mod, VIP, Discord Member)
- Beautiful witch-themed styling

Closes #45

api/src/app/services/user.service.ts

@@ -6,6 +6,7 @@
 
 import { User } from "@library/shared-types";
 import { prisma } from "../lib/prisma";
+import { SuggestionStatus } from "@prisma/client";
 
 export class UserService {
   private prisma = prisma;
@@ -21,6 +22,10 @@ export class UserService {
       username: user.username,
       email: user.email,
       avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
       isAdmin: user.isAdmin,
       isBanned: user.isBanned,
       inDiscord: user.inDiscord,
@@ -45,6 +50,10 @@ export class UserService {
       username: user.username,
       email: user.email,
       avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
       isAdmin: user.isAdmin,
       isBanned: user.isBanned,
       inDiscord: user.inDiscord,
@@ -66,6 +75,10 @@ export class UserService {
       username: user.username,
       email: user.email,
       avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
       isAdmin: user.isAdmin,
       isBanned: user.isBanned,
       inDiscord: user.inDiscord,
@@ -87,6 +100,10 @@ export class UserService {
       username: user.username,
       email: user.email,
       avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
       isAdmin: user.isAdmin,
       isBanned: user.isBanned,
       inDiscord: user.inDiscord,
@@ -104,4 +121,137 @@ export class UserService {
 
     return user?.isBanned ?? false;
   }
+
+  async getUserBySlug(slug: string): Promise<User | null> {
+    const user = await this.prisma.user.findFirst({
+      where: { slug },
+    });
+
+    if (!user) {
+      return null;
+    }
+
+    return {
+      id: user.id,
+      discordId: user.discordId,
+      username: user.username,
+      email: user.email,
+      avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
+      isAdmin: user.isAdmin,
+      isBanned: user.isBanned,
+      inDiscord: user.inDiscord,
+      isVip: user.isVip,
+      isMod: user.isMod,
+      isStaff: user.isStaff,
+    };
+  }
+
+  async updateUserSettings(
+    id: string,
+    updates: {
+      slug?: string;
+      displayName?: string;
+      bio?: string;
+      profilePublic?: boolean;
+    }
+  ): Promise<User | null> {
+    const user = await this.prisma.user.update({
+      where: { id },
+      data: updates,
+    });
+
+    return {
+      id: user.id,
+      discordId: user.discordId,
+      username: user.username,
+      email: user.email,
+      avatar: user.avatar || undefined,
+      slug: user.slug || undefined,
+      displayName: user.displayName || undefined,
+      bio: user.bio || undefined,
+      profilePublic: user.profilePublic,
+      isAdmin: user.isAdmin,
+      isBanned: user.isBanned,
+      inDiscord: user.inDiscord,
+      isVip: user.isVip,
+      isMod: user.isMod,
+      isStaff: user.isStaff,
+    };
+  }
+
+  async getUserProfile(identifier: string): Promise<{
+    id: string;
+    username: string;
+    displayName?: string | null;
+    avatar?: string | null;
+    bio?: string | null;
+    slug?: string | null;
+    isStaff: boolean;
+    isMod: boolean;
+    isVip: boolean;
+    inDiscord: boolean;
+    profilePublic: boolean;
+    createdAt: Date;
+    stats: {
+      suggestionsCount: number;
+      suggestionsAcceptedCount: number;
+      likesCount: number;
+      commentsCount: number;
+    };
+  } | null> {
+    // Try to find by slug first, then by id if it's a valid ObjectId
+    const isValidObjectId = /^[0-9a-f]{24}$/i.test(identifier);
+
+    const whereConditions = isValidObjectId
+      ? [{ slug: identifier }, { id: identifier }]
+      : [{ slug: identifier }];
+
+    const user = await this.prisma.user.findFirst({
+      where: {
+        OR: whereConditions,
+      },
+      include: {
+        suggestions: {
+          select: { id: true, status: true },
+        },
+        likes: {
+          select: { id: true },
+        },
+        comments: {
+          select: { id: true },
+        },
+      },
+    });
+
+    if (!user) {
+      return null;
+    }
+
+    return {
+      id: user.id,
+      username: user.username,
+      displayName: user.displayName,
+      avatar: user.avatar,
+      bio: user.bio,
+      slug: user.slug,
+      isStaff: user.isStaff,
+      isMod: user.isMod,
+      isVip: user.isVip,
+      inDiscord: user.inDiscord,
+      profilePublic: user.profilePublic,
+      createdAt: user.createdAt,
+      stats: {
+        suggestionsCount: user.suggestions.length,
+        suggestionsAcceptedCount: user.suggestions.filter(
+          (suggestion) => suggestion.status === SuggestionStatus.ACCEPTED
+        ).length,
+        likesCount: user.likes.length,
+        commentsCount: user.comments.length,
+      },
+    };
+  }
 }