Add setter for times attribute to support light travel time corrections

[Amityush-lgtm]

PR Description

Adds a setter for the times property in GenericSpectrogram to enable users to update time coordinates. This allows for light travel time corrections when comparing data from multiple spacecraft at different distances (e.g., Solar Orbiter RPW and Parker Solar Probe).
Closes #77

What changed

• Added a times setter in radiospectra/spectrogram/spectrogrambase.py

  • Accepts astropy.time.Time
  • Also accepts time-like astropy.units.Quantity (e.g., 500 * u.s) and applies it as an offset to the existing Time array
  • Validates length matches the current time axis
  • Validates inputs are time-compatible
  • Updates meta["start_time"] / meta["end_time"] to stay consistent with the updated axis

• Added unit tests in radiospectra/tests/test_spectrogrambase.py covering:

  • setting Time directly
  • applying a Quantity offset
  • metadata updates
  • error cases (wrong length, invalid type, incompatible units)

Example

Before:

spec.times = spec.times + 500*u.s  # AttributeError

After:

import astropy.units as u
spec.times = spec.times + 500*u.s 
# Metadata automatically updated

@samaloney @hayesla

[Amityush-lgtm]

Hi @samaloney,

I’ve updated the PR to address the initial CI failures (renamed the changelog to #140 and fixed the linting issues).

The remaining CI failures in radiospectra.net.sources.tests appear to be pre-existing and unrelated to this PR. I confirmed this by running the test suite on a clean checkout of upstream/main and seeing the same failures.

These failures seem to be due to recent breaking changes in sunpy 7.1.0’s Scraper class that the radiospectra network clients haven’t accounted for yet. The changes in spectrogrambase.py and the new tests added in this PR are passing as expected.

Let me know if you’d like me to open a separate issue for the SunPy compatibility problem or if there’s anything else you’d like me to adjust here.

Thanks!