chore(repo): restructure as monorepo with server and client workspaces

- move NestJS app into server/ subdirectory
- add client/ React+TypeScript (Vite) app with Hello World
- update docker-compose to build and run both services
- add root package.json declaring npm workspaces
- update .gitignore to cover node_modules and dist at all depths

server/src/common/dto/pagination.dto.ts

@@ -0,0 +1,40 @@
+import { ApiPropertyOptional } from "@nestjs/swagger";
+import { Type } from "class-transformer";
+import { IsIn, IsInt, IsOptional, IsString, Min } from "class-validator";
+
+export class PaginationQueryDto<TOrderBy extends string = string> {
+  @ApiPropertyOptional({ example: 1, default: 1 })
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(1)
+  page?: number = 1;
+
+  @ApiPropertyOptional({ example: 20, default: 20 })
+  @IsOptional()
+  @Type(() => Number)
+  @IsInt()
+  @Min(1)
+  limit?: number = 20;
+
+  @ApiPropertyOptional({
+    example: "id",
+    default: "id",
+    description: "Field to order by",
+  })
+  @IsOptional()
+  @IsString()
+  orderBy?: TOrderBy;
+
+  @ApiPropertyOptional({ enum: ["ASC", "DESC"], default: "ASC" })
+  @IsOptional()
+  @IsIn(["ASC", "DESC"])
+  orderDir?: "ASC" | "DESC" = "ASC";
+}
+
+export interface PaginatedResult<T> {
+  data: T[];
+  total: number;
+  page: number;
+  limit: number;
+}

server/src/common/trace-context.ts

@@ -0,0 +1,11 @@
+import { AsyncLocalStorage } from "async_hooks";
+
+export interface TraceStore {
+  traceId: string;
+}
+
+export const traceStorage = new AsyncLocalStorage<TraceStore>();
+
+export function getTraceId(): string | undefined {
+  return traceStorage.getStore()?.traceId;
+}

server/src/common/trace-logger.ts

@@ -0,0 +1,31 @@
+import { ConsoleLogger, ConsoleLoggerOptions, LogLevel } from "@nestjs/common";
+import { getTraceId } from "./trace-context";
+
+export class TraceLogger extends ConsoleLogger {
+  constructor(context?: string, options: ConsoleLoggerOptions = {}) {
+    super(context as string, options);
+  }
+
+  protected override getTimestamp(): string {
+    return new Date().toISOString();
+  }
+
+  protected override formatMessage(
+    logLevel: LogLevel,
+    message: unknown,
+    _pidMessage: string,
+    _formattedLogLevel: string,
+    contextMessage: string,
+    timestampDiff: string,
+  ): string {
+    const output = this.stringifyMessage(message, logLevel);
+    const level = this.colorize(logLevel.toUpperCase(), logLevel);
+    return `${this.getTimestamp()} ${level} ${contextMessage}${output}${timestampDiff}\n`;
+  }
+
+  protected override formatContext(context: string): string {
+    const traceId = getTraceId();
+    const traced = traceId ? `${context}:${traceId}` : context;
+    return super.formatContext(traced);
+  }
+}