Fix map to world coordinate conversion

[HovorunBh]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses
Primary OS tested on	Ubuntu
Robotic platform tested on	(Steve's Robot, gazebo simulation of Tally, hardware turtlebot)
Does this PR contain AI generated software?	No

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Description of contribution in a few bullet points

For reproducing the issue see the test I added

We noticed that ComputePathThroughPoses with SmacPlannerHybrid when asked to generate path through poses that are on the same line (in this example: [{x: 2, y: 0}, {x: 4, y: 0}, {x: 6, y: 0}]) generates path like this:

It is assumed that end of path1 is the start of path2, but when end of path1 is converted from map to world, and then back to map it ends up in a different costmap cell.

When we convert world to map coordinates we add 0.5

Therefore when we convert map to world I think we should subtract 0.5. Otherwise we end up in the next costmap cell With this change path looks like more straight:

Description of documentation updates required from your changes

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Future work that may be required in bullet points

For Maintainers:

• [ ] Check that any new parameters added are updated in docs.nav2.org
• [ ] Check that any significant change is added to the migration guide
• [ ] Check that any new features OR changes to existing behaviors are reflected in the tuning guide
• [ ] Check that any new functions have Doxygen added
• [ ] Check that any new features have test coverage
• [ ] Check that any new plugins is added to the plugins page
• [ ] If BT Node, Additionally: add to BT's XML index of nodes for groot, BT package's readme table, and BT library lists

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Files	Coverage Δ
...2_smac_planner/include/nav2_smac_planner/utils.hpp	98.64% <100.00%> (ø)

... and 2 files with indirect coverage changes

[SteveMacenski]

Thanks! All good points, well explained, and with visual examples!