refactor: restructure to clean architecture

fix: restore ScoringConfig improvements lost in refactor commit

docs: rewrite README and CLAUDE.md to reflect current architecture

code-format

code fixes

import-portfolio.js

@@ -0,0 +1,34 @@
+// import-portfolio.js
+//
+// Imports holdings from a broker CSV export into portfolio.json.
+//
+// Usage:
+//   npm run import-portfolio -- holdings.csv
+//
+// Supported brokers (auto-detected from headers):
+//   Robinhood  → Account → Statements & History → Export → Holdings
+//   Vanguard   → My Accounts → Holdings → Download (top-right icon)
+//   Fidelity   → Accounts & Trade → Portfolio → Positions → Download CSV
+//
+// If you have multiple brokers, run the command once per file —
+// each import merges into portfolio.json without overwriting previous entries.
+
+import { PortfolioImporter } from './src/finance/PortfolioImporter.js';
+
+const csvPath = process.argv[2];
+
+if (!csvPath) {
+  console.error('Usage: npm run import-portfolio -- <path-to-csv>');
+  console.error('');
+  console.error('Examples:');
+  console.error('  npm run import-portfolio -- ~/Downloads/robinhood_holdings.csv');
+  console.error('  npm run import-portfolio -- ~/Downloads/vanguard_holdings.csv');
+  process.exit(1);
+}
+
+try {
+  new PortfolioImporter().import(csvPath);
+} catch (err) {
+  console.error(`\n======>>>> Import failed <<<<====== ${err.message}`);
+  process.exit(1);
+}