feat: implement DigitalOcean serverless function for Square product sync

[KK578]

This PR introduces a DigitalOcean Serverless Function to run the Square Product Synchronizer pipeline in Node.js instead of within the Blazor server. It utilizes the project.yml configuration and runs via the pg and square NPM packages under packages/square/product-sync. The environment variables are safely managed outside of source control.

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PR created automatically by Jules for task 9331240963927146706 started by @KK578

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[coveralls]

Pull Request Test Coverage Report for Build 22929403838

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 76.552%

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Totals
Change from base Build 4578175021:	0.0%
Covered Lines:	1628
Relevant Lines:	2068

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💛 - Coveralls