Inadequate caching implementation in FpDefaultTest.java

[0pdd]

The puzzle 4840-a0c46596 from #4840 has to be resolved:

eo/eo-maven-plugin/src/test/java/org/eolang/maven/FpDefaultTest.java

Lines 386 to 391 in 7148c77

	* @todo #4840:90min Implement proper cache validation mechanism.
	* Currently, FpDefault relies on file timestamps to decide whether to use
	* the cache or not. This approach is not reliable in many cases.
	* For example, in the transpilation step, the source files are often
	* modified right before transpilation, making the cache always older
	* than the source files.

The puzzle was created by Yegor Bugayenko on 02-Feb-26.

Estimate: 90 minutes, role: DEV.

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