core: fix path projection on backward chunks

[eckter]

Fix #5037

[Erashin]

Modulo UnitTests to fix, LGTM!

[codecov]

Codecov Report

Merging #5060 (b37fc6e) into dev (04b21aa) will increase coverage by 0.00%.
Report is 3 commits behind head on dev.
The diff coverage is 90.90%.

@@            Coverage Diff            @@
##                dev    #5060   +/-   ##
=========================================
  Coverage     22.00%   22.01%           
- Complexity     2450     2455    +5     
=========================================
  Files           852      852           
  Lines         89252    89261    +9     
  Branches       2480     2482    +2     
=========================================
+ Hits          19639    19647    +8     
  Misses        68254    68254           
- Partials       1359     1360    +1     

Flag	Coverage Δ
core	79.46% <90.90%> (+<0.01%)	⬆️

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Files Changed	Coverage Δ
...srd/api/pathfinding/PathfindingBlocksEndpoint.java	88.33% <85.71%> (-0.18%)	⬇️
.../fr/sncf/osrd/sim_infra/impl/PathPropertiesImpl.kt	91.91% <100.00%> (+0.25%)	⬆️