Add Bonanza Produce multi-invoice statement template

- Added multi-invoice template for Bonanza Produce with :multi and :multi-match? flags
- Template uses keywords for statement header to identify multi-invoice format
- Extracts invoice-number, date, customer-identifier (from RETURN line), and total
- Parses 4 invoices from statement PDF 13595522.pdf
- All tests pass (29 assertions, 0 failures, 0 errors)

- Added test: parse-bonanza-produce-statement-13595522
- Updated invoice-template-creator skill: emphasized test-first approach

.claude/skills/invoice-template-creator/SKILL.md

@@ -146,7 +146,7 @@ The `(?s)` flag makes `.` match newlines. Use non-greedy `+?` and lookaheads `(?
 
 ## Testing Best Practices
 
-1. **Start with a failing test** - Define expected values before implementing
+1. IMPORTANT, CRITICAL!! **Start with a failing test** - Define expected values before implementing
 2. **Test actual PDF parsing** - Use `parse-file` or `parse` with real PDF text
 3. **Verify each field individually** - Separate assertions for clarity
 4. **Handle date comparisons carefully** - Compare year/month/day separately if needed