Convert XvcEntity to (u64, u64) to fix branch related possible problems

[iesahin]

The first part of the tuple is the same as previous, while the second u64 is generated randomly for each command invocation. This makes entities unique and also sorted.

Close #89
Close #88

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[codecov]

Codecov Report

Base: 67.64% // Head: 66.56% // Decreases project coverage by -1.08% ⚠️

Coverage data is based on head (bc1846e) compared to base (5aad752).
Patch coverage: 78.25% of modified lines in pull request are covered.

❗ Current head bc1846e differs from pull request most recent head 2931bdd. Consider uploading reports for the commit 2931bdd to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #201      +/-   ##
==========================================
- Coverage   67.64%   66.56%   -1.08%     
==========================================
  Files          93       96       +3     
  Lines        9423     9653     +230     
==========================================
+ Hits         6374     6426      +52     
- Misses       3049     3227     +178     

Impacted Files	Coverage Δ
core/src/check_ignore/mod.rs	11.84% <ø> (ø)
core/src/lib.rs	100.00% <ø> (ø)
core/src/types/cachetype.rs	60.00% <ø> (-15.00%)	⬇️
core/src/types/hashalgorithm.rs	58.82% <ø> (-5.89%)	⬇️
core/src/types/xvcfiletype.rs	28.20% <0.00%> (-7.70%)	⬇️
core/src/types/xvcpath.rs	72.63% <0.00%> (-6.72%)	⬇️
core/src/util/file.rs	92.30% <ø> (+1.00%)	⬆️
core/src/util/mod.rs	0.00% <ø> (ø)
file/src/error.rs	5.35% <0.00%> (+5.35%)	⬆️
lib/src/lib.rs	12.50% <ø> (ø)
... and 119 more

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