feat: Add Invoice management feature (full-stack CRUD)

[devin-ai-integration]

Summary

Adds a complete Invoice management feature following JHipster entity generation conventions. Users can create, view, edit, and delete invoices through both the REST API and Angular frontend.

Invoice Entity Fields

• number (String, required) - Invoice identifier
• date (LocalDate, required) - Invoice date
• dueDate (LocalDate, required) - Payment due date
• amount (BigDecimal, required) - Invoice amount
• status (enum: DRAFT/SENT/PAID/OVERDUE, required) - Invoice status
• bankAccount (ManyToOne relationship) - Linked bank account

Backend (Spring Boot)

• Invoice.java - JPA entity with validation constraints and fluent API
• InvoiceStatus.java - Enum for invoice statuses
• InvoiceRepository.java - Spring Data JPA repository with eager relationship loading
• InvoiceResource.java - REST controller with full CRUD (POST/GET/PUT/PATCH/DELETE)
• Liquibase changelogs for table creation, FK constraint, and sample data
• 22 JUnit tests passing (InvoiceResourceIT: 20 tests, InvoiceTest: 2 tests)

Frontend (Angular)

• Invoice model with dayjs date types and InvoiceStatus type
• InvoiceService with date serialization/deserialization
• List view with sortable columns, date formatting, and status translation
• Detail view showing all fields with bank account link
• Create/Edit form with datepickers, status dropdown, and bank account selector
• Delete confirmation dialog
• Route configuration with lazy loading and resolver
• i18n translations (English) for all labels, statuses, and messages
• Navbar menu entry under Entities

Review & Testing Checklist for Human

• Start the app (./mvnw or ./npmw run backend:start + ./npmw run start) and verify the Invoice menu item appears in the navbar under Entities
• Create a new invoice with all fields filled, confirm it persists correctly
• Verify the list view shows all invoices with correct date formatting and status labels
• Edit an existing invoice and confirm changes are saved
• Delete an invoice and confirm it is removed from the list
• Verify the bank account dropdown in the create/edit form loads existing bank accounts
• Run ./mvnw test to confirm all backend tests pass

Notes

• Uses LocalDate for date/dueDate fields (more natural for invoice dates than Instant)
• Follows exact JHipster 9 conventions: entity patterns, needle comments, fluent setters, cache strategy, etc.
• Requires Java 21+ to build (enforced by Maven enforcer plugin)

Link to Devin session: https://partner-workshops.devinenterprise.com/sessions/02222c4302344b1abd05122a96b526ef

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[devin-ai-integration]

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[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

View in Devin Review to see 4 additional findings.