Use DevRev APIs for uploading artifacts and add new fields to EventContext interface (#39)

## Summary
- Add three new optional fields `extract_from`, `initial_sync_scope` and
`reset_extraction` to the `EventContext` interface to enable time-scoped
syncs.
- Use DevRev API endpoints to prepare and upload artifacts.

## Related Issues
- work-item: https://app.devrev.ai/devrev/works/ISS-167979
- work-item: https://app.devrev.ai/devrev/works/ISS-149972

## Type of Change
- [ ] Change doesn't affect products or customers
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] Non-breaking change (the new functionality and code refactor do
not require a migration strategy)
- [ ] Breaking change (fix or feature that will require a migration plan
for data or other services)
- [ ] Documentation/comment update
- [ ] Other (please describe):

## Testing Procedure
- Run tests using `npm run test`.

## Checklist
- [ ] I used generative AI to generate this PR
- [x] I have self-reviewed my code for clarity and correctness
- [x] I have added or updated comments for complex or non-obvious logic
in my code
- [x] I have updated relevant documentation (e.g., README, code docs)
- [x] My changes do not introduce new warnings or errors
- [x] I have added or updated tests to cover new or changed
functionality
- [x] All tests pass locally with my changes applied

Author: patricijabrecko

CONTRIBUTING.md

@@ -0,0 +1,11 @@
+# Contributing
+
+All changes must be made through Pull Requests. Direct commits to main or release branches are not allowed.
+
+## Versioning
+
+We follow Semantic Versioning (SemVer) for versioning, with the format `MAJOR.MINOR.PATCH`.
+
+- `MAJOR` - Breaking changes, incompatible API changes
+- `MINOR` - New features, backward compatible
+- `PATCH` - Bug fixes, no new features

README.md

@@ -4,8 +4,7 @@
 
 ## Overview
 
-The Airdrop SDK for TypeScript helps developers build snap-ins that integrate with DevRev’s Airdrop platform. 
-This SDK simplifies the workflow for handling data extraction and loading, event-driven actions, state management, and artifact handling.
+The Airdrop SDK for TypeScript helps developers build snap-ins that integrate with DevRev’s Airdrop platform. This SDK simplifies the workflow for handling data extraction and loading, event-driven actions, state management, and artifact handling.
 
 It provides features such as: