Adds a new Cambodia localization package with core accounting setup, tax configuration, fiscal positions, tax reports, and support for EMV QR code payments. This helps Cambodian companies use Odoo accounting with country-specific structures and payment standards out of the box.

Implement a basic accounting package for Cambodia including:

- COA
- Account groups
- Tax groups
- Taxes
- Fiscal Positions
- Tax reports
- EMV QR Code for payment

task-4383330

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This adds a new Cambodia reporting module with key financial statements and a WT003 withholding tax export. Businesses operating in Cambodia can now produce localized balance sheet, profit and loss, and tax reporting outputs more directly in Odoo.

Adds basic reporting module for Cambodia, including:
- Balance sheet
- Profit & loss
- WT003 export

task-4383330