mnt/extract flight data exporters

[CameronBrooks11]

Pull request type

• Code maintenance (refactoring, formatting, tests)

Checklist

• Tests for the changes have been added (if needed)
• Docs have been reviewed and added / updated
• Lint (black rocketpy/ tests/) has passed locally
• All tests (pytest tests -m slow --runslow) have passed locally
• CHANGELOG.md has been updated (if relevant)

Current behavior

Export routines for Flight live as instance methods in rocketpy/simulation/flight.py (export_data, export_pressures, export_sensor_data, export_kml). This mixes simulation with I/O concerns and forces an import-time dependency on simplekml for users who do not export.

New behavior

• Extracted exporters into a new class FlightDataExporter at rocketpy/simulation/flight_data_exporter.py.
• Added deprecation wrappers on Flight methods that delegate to FlightDataExporter and emit DeprecationWarning with migration guidance.
• Re-exported FlightDataExporter in rocketpy/simulation/__init__.py.
• No functional changes to outputs or signatures aside from deprecation.
• Deprecation schedule: wrappers remain until v1.12.0.
• Migration example:

from rocketpy.simulation import FlightDataExporter

exporter = FlightDataExporter(test_flight)
exporter.export_data("out.csv", "angle_of_attack", "mach_number")

Breaking change

• No

Additional information

• Local runs show deprecation warnings during integration tests where legacy methods are exercised. Example: Moved to FlightDataExporter.export_data() and will be removed in v1.12.0.
• Headless plotting for integration tests was configured with MPLBACKEND=Agg.
• Formatting-only changes were intentionally excluded from this PR to keep the diff focused on the refactor.

[Gui-FernandesBR]

I really like what I see here... I will take a look at it asap

[codecov]

Codecov Report

❌ Patch coverage is 82.00000% with 18 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.12%. Comparing base (f17893b) to head (1ec0f48).
⚠️ Report is 21 commits behind head on develop.

Files with missing lines	Patch %	Lines
rocketpy/simulation/flight_data_exporter.py	79.54%	18 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #845      +/-   ##
===========================================
+ Coverage    80.02%   80.12%   +0.09%     
===========================================
  Files           98      104       +6     
  Lines        12004    12552     +548     
===========================================
+ Hits          9606    10057     +451     
- Misses        2398     2495      +97     

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[CameronBrooks11]

Sounds good, let me know if there's anything that needs to be done or revised before this can be merged to develop...I have some enhancements of the kml export I have in the works and I'd rather not stack the PR branches and have to deal with rebasing later if we can help it :)

[CameronBrooks11]

@Gui-FernandesBR Sorry if this PR disappeared for a few days...my account got false flagged by the GitHub bots