feat: Implement supplier export functionality with workbook generation

- Add `writeSupplierWorkbook` function to create Excel workbooks for supplier analysis results.
- Introduce `SupplierExportSummary` type for summarizing export data.
- Create tests for `writeSupplierWorkbook` to ensure correct sheet creation and data population.
- Implement supplier scoring logic in `supplier-scoring.ts` to evaluate product profitability and demand.
- Add tests for supplier scoring to validate scoring logic and verdict determination.
- Enhance UPC file analysis to integrate supplier scoring and export results to Excel.
- Update database writing logic to accommodate new supplier analysis results.
- Refactor types to include supplier-specific data structures and scoring metrics.
- Ensure proper cleanup of temporary files after tests.

src/index.ts

@@ -10,7 +10,7 @@ import {
 import path from "node:path";
 import type { AnalysisResult } from "./types.ts";
 
-const DB_PATH = "./results.db";
+const DB_PATH = process.env.RESULTS_DB_PATH || path.join("db", "results.db");
 const INPUT_BATCH_SIZE = 50;
 
 function parseSellabilityArg(args: string[]): SellabilityFilter {
@@ -59,7 +59,7 @@ function resolveBaseOutputPath(inputFile: string, outputFile?: string): string {
   if (outputFile) return outputFile;
 
   const parsedInput = path.parse(inputFile);
-  return path.join(parsedInput.dir, `${parsedInput.name}_results.xlsx`);
+  return path.join("output", `${parsedInput.name}_results.xlsx`);
 }
 
 async function main() {