Refactor DI for simplicity and type safety

This commit improves the dependency injection mechanism by introducing a
custom `injectKey` function.

Key improvements are:

- Enforced type consistency during dependency registration and
  instantiation.
- Simplified injection process, abstracting away the complexity with a
  uniform API, regardless of the dependency's lifetime.
- Eliminated the possibility of `undefined` returns during dependency
  injection, promoting fail-fast behavior.
- Removed the necessity for type casting to `symbol` for injection keys
  in unit tests by using existing types.
- Consalidated imports, combining keys and injection functions in one
  `import` statement.

tests/unit/infrastructure/CodeRunner.spec.ts

@@ -2,7 +2,7 @@ import { describe, it, expect } from 'vitest';
 import { RuntimeEnvironmentStub } from '@tests/unit/shared/Stubs/RuntimeEnvironmentStub';
 import { OperatingSystem } from '@/domain/OperatingSystem';
 import { CodeRunner } from '@/infrastructure/CodeRunner';
-import { expectThrowsAsync } from '@tests/unit/shared/Assertions/ExpectThrowsAsync';
+import { expectThrowsAsync } from '@tests/shared/Assertions/ExpectThrowsAsync';
 import { SystemOperationsStub } from '@tests/unit/shared/Stubs/SystemOperationsStub';
 import { OperatingSystemOpsStub } from '@tests/unit/shared/Stubs/OperatingSystemOpsStub';
 import { LocationOpsStub } from '@tests/unit/shared/Stubs/LocationOpsStub';