[PT1-207] Remove yarn and setup pure forge

[zZoMROT]

Change Summary

What does this PR change?
Remove yarn and setup repo as pure forge

Related Issue/Ticket:
JIRA ticket

Testing & Verification

How was this tested?

• Unit tests
• Integration tests
• Manual testing (describe steps)
• Verified on staging

Manual check steps:

1. clone repo
2. checkout to the branch remove-yarn
3. run forge install
4. run forge build
5. run forge test

Risk Assessment

Risk Level:

• Low - Minor changes, no operational impact
• Medium - Moderate changes, limited impact, standard rollback available
• High - Significant changes, potential operational impact, complex rollback

Risks & Impact
Install dependencies without yarn, no risk