BUG/MNT: pre-release v1.13.0 review fixes

[Gui-FernandesBR]

Pull request type

• Code changes (bugfix, features)
• Code maintenance (refactoring, formatting, tests)
• ReadMe, Docs and GitHub updates

Summary

Fixes surfaced by the final pre-release code review of v1.13.0 (diff v1.12.1..master), plus the follow-ups from the codecov/patch failure and the GitHub Copilot review on this PR. All changed areas pass their unit/integration tests locally; lint + format clean.

Blocker

• rocketpy[animation] was missing imageio — animate_trajectory(export_file=...) calls plotter.open_gif/open_movie, which import imageio (not a core pyvista dependency), so the documented install path raised ImportError on every GIF/MP4 export. Added imageio to the animation extra.

Bug fixes / regressions

• 2-point akima Function crashed (IndexError at construction) — now reduces to linear interpolation (regression vs v1.12.1). Regression test added.
• Variadic parachute triggers (lambda *args:) raised TypeError instead of running — restored pre-1.13 behaviour (pressure, height, state, sensors).
• GEFS/HIRESW pressure factor was only matched against input_file, missing the realistic download path (model name arrives as input_dict); could yield pressures 100× too small. Also accept "mb"/"millibar" units.
• Environment.from_dict left ensemble_member unset after decoding an ensemble model (AttributeError) — now persisted/restored via to_dict.
• RingClusterMotor.info() printed the single base motor's thrust/impulse instead of the N×-scaled cluster values — delegates to super().info().

Copilot review follow-ups

• Planning the upload to GitHub #1 / Preparing the project for Git #2 — test coverage: added tests for the variadic-trigger arities and the ensemble_member round-trip (also fixes the codecov/patch gap that failed this PR).
• Uploading your project #3 — pressure-unit consistency: an explicit pressure_conversion_factor="mb" was rejected while files could auto-detect "mb". Centralised the unit→factor logic in a single pressure_unit_to_factor helper (environment.tools) reused by the validator, the explicit-factor mapping and file auto-detection.

Docs

• Plotly chart on the examples index rendered blank: the jupyter-execute block called fig.show() with no renderer, so plotly emitted a mimetype bundle a static HTML page can't display. Set the renderer to notebook_connected (CDN plotly.js).

Quality

• fit_pchip no longer emits a spurious RuntimeWarning: divide by zero on flat data.
• Removed a redundant nested kwargs.pop(...) in animate_trajectory.
• Changelog: fixed rocketpy.utils → rocketpy.utilities, added Changed notes for the akima / differentiate behaviour changes, dropped the stray MNT: pre-release v1.13.0 cleanup — changelog consolidation + optional deps sync #1073 entry.

Known follow-up (deliberately not in this PR)

• PyVista Plotter cleanup on error paths: the plotter created in animate_trajectory/animate_rotate is only guaranteed to be .close()d once _run_animation is entered; a failure during scene-building leaks it until GC. A proper fix needs wrapping ~350 lines of scene construction in try/except — riskier than the bounded leak for a release, so left as a follow-up.
• Test-suite flakiness under pytest-randomly (order-dependent failures, unrelated to these changes) is worth a separate stabilization issue.

Breaking change

• No

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.36%. Comparing base (10fa378) to head (dd0af43).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1074      +/-   ##
===========================================
+ Coverage    82.29%   82.36%   +0.06%     
===========================================
  Files          122      122              
  Lines        16361    16377      +16     
===========================================
+ Hits         13465    13489      +24     
+ Misses        2896     2888       -8     

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[Copilot]

Pull request overview

Release-hardening fixes for the RocketPy v1.13.0 pre-release review, spanning packaging, regression/compatibility fixes, numerical robustness, and changelog updates.

Changes:

• Fix Akima interpolation for the 2-point edge case (fallback to linear) and add a regression unit test.
• Restore compatibility for variadic parachute triggers and correct a few environment serialization / pressure-unit handling paths.
• Clean up minor quality issues (PCHIP warning suppression, animation kwargs pop, ring cluster info() output) and update release notes + optional deps.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
tests/unit/mathutils/test_function.py	Adds regression coverage for 2-point Akima interpolation.
rocketpy/mathutils/_calc/_fitting.py	Fixes 2-point Akima construction and silences harmless PCHIP divide-by-zero warnings.
rocketpy/rocket/parachute.py	Restores support for variadic (*args) trigger callables via signature inspection.
rocketpy/environment/tools.py	Expands pressure level unit auto-detection to include mb/millibar variants.
rocketpy/environment/environment.py	Improves model-name based pressure conversion detection and persists ensemble_member in (de)serialization.
rocketpy/plots/flight_plots.py	Removes redundant nested kwargs.pop(...) in animation options.
rocketpy/motors/ring_cluster_motor.py	Makes RingClusterMotor.info() report cluster-scaled quantities via super().info().
pyproject.toml	Adds imageio to the animation extra to prevent export-time ImportError.
CHANGELOG.md	Cleans up an incorrect module reference and adds “Changed” notes for Function behavior updates.