feat: remove old farm config (#10601)

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## PR-Codex overview
This PR focuses on restructuring the farms configuration files and
updating references in the codebase.

### Detailed summary
- Moved farms configuration files to `src/farms`
- Updated imports in various files to reflect the new file structure
- Renamed `farmsV3ConfigChainMap` to `legacyFarmsV3ConfigChainMap`
- Removed deprecated farms configuration objects and exports

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