fix: reject negative weights/quantities and out-of-range percentages

None of these numeric business fields had a lower bound, so a
negative honey weight, jar count, feeding amount, mite count, or
stock quantity was silently accepted - each would corrupt whatever
total or statistic it later feeds into. Added @Min(0):

- Harvest: honeySuperCount, grossWeight, netWeight
- HoneyBatch: amount (+ @Max(100) on waterContent, a percentage)
- HoneyMeasurement: waterContent (+ @Max(100))
- Feeding: amount
- Extraction: amount (+ @Max(100) on waterContent)
- StockItem: quantity, minThreshold
- VarroaMeasurement: durationMinutes, miteCount, calculatedValue

Left temperature fields alone (extraction, inspection) - genuinely
can be negative (winter inspections, outdoor storage) and no
confident domain bound exists to apply instead. Update DTOs for these
entities all extend PartialType(PickType(Create...Dto, [...])) from
@nestjs/swagger, which preserves validation decorators, so no
separate change was needed there.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

ApiCore-Backend/src/varroa/dto/create-varroa-measurement.dto.ts

@@ -6,6 +6,7 @@ import {
   IsNumber,
   IsOptional,
   IsString,
+  Min,
 } from 'class-validator';
 import { VarroaMethod } from '../../../generated/prisma';
 
@@ -25,16 +26,19 @@ export class CreateVarroaMeasurementDto {
   @ApiPropertyOptional()
   @IsOptional()
   @IsInt()
+  @Min(0)
   durationMinutes?: number;
 
   @ApiPropertyOptional()
   @IsOptional()
   @IsInt()
+  @Min(0)
   miteCount?: number;
 
   @ApiPropertyOptional()
   @IsOptional()
   @IsNumber()
+  @Min(0)
   calculatedValue?: number;
 
   @ApiPropertyOptional()