✨ feat(api-gateway): add Swagger, admin endpoints, and scheduler

- Add Swagger/OpenAPI documentation at /docs endpoint
- Add admin module for system-wide API key management
- Add scheduler for monthly credit reset and usage cleanup
- Add Docker Compose entry for Mac Mini deployment
- Document all endpoints with descriptions and examples

services/mana-api-gateway/src/usage/dto/usage-query.dto.ts

@@ -1,7 +1,14 @@
 import { IsOptional, IsString, IsDateString, IsInt, Min, Max } from 'class-validator';
 import { Transform } from 'class-transformer';
+import { ApiPropertyOptional } from '@nestjs/swagger';
 
 export class UsageQueryDto {
+	@ApiPropertyOptional({
+		description: 'Number of days to query (1-365)',
+		minimum: 1,
+		maximum: 365,
+		default: 30,
+	})
 	@IsOptional()
 	@Transform(({ value }) => parseInt(value, 10))
 	@IsInt()
@@ -9,14 +16,26 @@ export class UsageQueryDto {
 	@Max(365)
 	days?: number = 30;
 
+	@ApiPropertyOptional({
+		description: 'Start date for custom range (ISO 8601)',
+		example: '2025-01-01',
+	})
 	@IsOptional()
 	@IsDateString()
 	startDate?: string;
 
+	@ApiPropertyOptional({
+		description: 'End date for custom range (ISO 8601)',
+		example: '2025-01-31',
+	})
 	@IsOptional()
 	@IsDateString()
 	endDate?: string;
 
+	@ApiPropertyOptional({
+		description: 'Filter by endpoint',
+		example: 'search',
+	})
 	@IsOptional()
 	@IsString()
 	endpoint?: string;