fix: resolve module resolution errors by replacing path aliases with relative imports

- Replace all @/ path aliases with proper relative imports and .js extensions
- Update @mollie/api-client peer dependency to support v4.x (^3.7.0 || ^4.0.0)
- Bump version to 0.1.5
- Ensure ESM compatibility for plugin distribution

Fixes module resolution error: "Cannot find package '@/collections'" when using
the plugin in external PayloadCMS projects.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/collections/hooks.ts

@@ -1,6 +1,6 @@
-import type { Payment } from '@/plugin/types'
+import type { Payment } from '../plugin/types/index.js'
 import type { Payload } from 'payload'
-import { useBillingPlugin } from '@/plugin'
+import { useBillingPlugin } from '../plugin/index.js'
 
 export const initProviderPayment = (payload: Payload, payment: Partial<Payment>) => {
   const billing = useBillingPlugin(payload)

src/collections/index.ts

@@ -1,3 +1,3 @@
-export { createInvoicesCollection } from './invoices'
-export { createPaymentsCollection } from './payments'
-export { createRefundsCollection } from './refunds'
+export { createInvoicesCollection } from './invoices.js'
+export { createPaymentsCollection } from './payments.js'
+export { createRefundsCollection } from './refunds.js'

src/collections/invoices.ts

@@ -5,10 +5,10 @@ import {
   CollectionBeforeValidateHook,
   CollectionConfig, Field,
 } from 'payload'
-import type { BillingPluginConfig} from '@/plugin/config';
-import { defaults } from '@/plugin/config'
-import { extractSlug } from '@/plugin/utils'
-import type { Invoice } from '@/plugin/types/invoices'
+import type { BillingPluginConfig} from '../plugin/config.js';
+import { defaults } from '../plugin/config.js'
+import { extractSlug } from '../plugin/utils.js'
+import type { Invoice } from '../plugin/types/invoices.js'
 
 export function createInvoicesCollection(pluginConfig: BillingPluginConfig): CollectionConfig {
   const {customerRelationSlug, customerInfoExtractor} = pluginConfig

src/collections/payments.ts

@@ -1,9 +1,9 @@
 import type { AccessArgs, CollectionBeforeChangeHook, CollectionConfig, Field } from 'payload'
-import type { BillingPluginConfig} from '@/plugin/config';
-import { defaults } from '@/plugin/config'
-import { extractSlug } from '@/plugin/utils'
-import type { Payment } from '@/plugin/types/payments'
-import { initProviderPayment } from '@/collections/hooks'
+import type { BillingPluginConfig} from '../plugin/config.js';
+import { defaults } from '../plugin/config.js'
+import { extractSlug } from '../plugin/utils.js'
+import type { Payment } from '../plugin/types/payments.js'
+import { initProviderPayment } from './hooks.js'
 
 export function createPaymentsCollection(pluginConfig: BillingPluginConfig): CollectionConfig {
   const overrides = typeof pluginConfig.collections?.payments === 'object' ? pluginConfig.collections?.payments : {}

src/collections/refunds.ts

@@ -1,7 +1,7 @@
 import type { AccessArgs, CollectionConfig } from 'payload'
-import { BillingPluginConfig, defaults } from '@/plugin/config'
-import { extractSlug } from '@/plugin/utils'
-import { Payment } from '@/plugin/types'
+import { BillingPluginConfig, defaults } from '../plugin/config.js'
+import { extractSlug } from '../plugin/utils.js'
+import { Payment } from '../plugin/types/index.js'
 
 export function createRefundsCollection(pluginConfig: BillingPluginConfig): CollectionConfig {
   // TODO: finish collection overrides