fix(fms): use station declination when required for terminal procedures

[BlueberryKing]

Fixes #[issue_no]

Summary of Changes

Another day, another magvar issue.

• Makes sure to use the station declination to compute the true radial bearing for CR/VR legs referencing a VOR navaid.
• Also fixes an issue where two discontinuities would exist in the flight plan after removing a departure transition. This happened because the flight plan was not restrung when the transition was removed, so both the discontinuity between sid and en route transition as well as the discontinuity between en route transition and en route segment persisted.

Screenshots (if necessary)

References

Additional context

Discord username (if different from GitHub):

Testing instructions

• Try one of
  • KEWR/04L EWR 5,
  • EGGP/09 POL 5V,
  • FACT/19 OKTED 1C,
  • LDDU/29 BEVIS 3D
  • LGAV/03L ROPOX 1D
  • LIMC/35L IPCUC 7F
  • or any other procedure you know of containing a CR/VR leg
• Make sure that all fixes are where you would expect them according to the chart.
• Enter a flight plan with a departure transition (common in the US). Remove the departure transition, make sure you only see one discontinuity in the flight plan.

How to download the PR for QA

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[BlueberryKing]

This is only available in MSFS2024. Should we fill this with the WMM value in 2020?