chore: project reorganization

[EvgeniiZaitsevCW]

Main changes

1. Some contracts and interfaces have been merged and renamed to reduce the number of files and simplify the contracts structure:
   • ICreditLineConfigurable + ICreditLine => ICreditLine.
   • ILiquidityPoolAccountable + ILiquidityPool => ILiquidityPool.
   • CreditLineConfigurable + CreditLineConfigurableUUPS => CreditLine.
   • LiquidityPoolAccountable + LiquidityPoolAccountableUUPS => LiquidityPool.
   • LendingMarket + LendingMarketUUPS => LendingMarket.
2. The type definition (structures and enums) of the credit line contract has been moved to the separate ICreditLineTypes interface.
3. Some intermediate sub-folders have been removed to make the contracts file structures less complex. The new structure is on the screenshot:
   
4. The style of comments has been unified within all files. For some structures and enums the field descriptions have been move to the comment above the entity.
5. NO changes have been made to the smart-contract logic and functions.
6. The following mock smart-contracts have been simplified for the following contracts: credit line, liquidity pool, lending market.
7. Unit tests have been changed accordingly to the reorganization of the smart-contract files. The tests for mock contracts mentioned in the previous point have been removed as they are no longer needed.

Versioning

The new version of the smart-contracts is 1.8.0.

Test Coverage

Test coverage details

File	% Stmts	% Branch	% Funcs	% Lines
contracts/	100.00	98.31	100.00	100.00
├─ CreditLine.sol	100.00	97.37	100.00	100.00
├─ LendingMarket.sol	100.00	99.12	100.00	100.00
├─ LendingMarketStorage.sol	100.00	100.00	100.00	100.00
├─ LiquidityPool.sol	100.00	97.22	100.00	100.00
contracts/base/	100.00	100.00	100.00	100.00
├─ AccessControlExtUpgradeable.sol	100.00	100.00	100.00	100.00
├─ UUPSExtUpgradeable.sol	100.00	100.00	100.00	100.00
├─ Versionable.sol	100.00	100.00	100.00	100.00
contracts/interfaces/	100.00	100.00	100.00	100.00
├─ ICreditLine.sol	100.00	100.00	100.00	100.00
├─ ICreditLineTypes.sol	100.00	100.00	100.00	100.00
├─ ILendingMarket.sol	100.00	100.00	100.00	100.00
├─ ILiquidityPool.sol	100.00	100.00	100.00	100.00
├─ IVersionable.sol	100.00	100.00	100.00	100.00
contracts/libraries/	100.00	70.00	100.00	100.00
├─ ABDKMath64x64.sol	100.00	65.91	100.00	100.00
├─ Constants.sol	100.00	100.00	100.00	100.00
├─ Error.sol	100.00	100.00	100.00	100.00
├─ InterestMath.sol	100.00	100.00	100.00	100.00
├─ Loan.sol	100.00	100.00	100.00	100.00
├─ Round.sol	100.00	100.00	100.00	100.00
├─ SafeCast.sol	100.00	100.00	100.00	100.00
contracts/mocks/	100.00	100.00	100.00	100.00
├─ AccessControlExtUpgradeableMock.sol	100.00	100.00	100.00	100.00
├─ CreditLineMock.sol	100.00	100.00	100.00	100.00
├─ ERC20Mock.sol	100.00	100.00	100.00	100.00
├─ LendingMarketMock.sol	100.00	100.00	100.00	100.00
├─ LiquidityPoolMock.sol	100.00	100.00	100.00	100.00
├─ RoundingMock.sol	100.00	100.00	100.00	100.00
├─ UUPSExtUpgradableMock.sol	100.00	100.00	100.00	100.00
contracts/testables/	100.00	100.00	100.00	100.00
├─ CreditLineTestable.sol	100.00	100.00	100.00	100.00
├─ LendingMarketTestable.sol	100.00	100.00	100.00	100.00
-----------------------------------------	----------	----------	----------	----------
All files	100.00	95.42	100.00	100.00
-----------------------------------------	----------	----------	----------	----------