Fix SWE L1b: prevent None propagation when no full science cycles found

[Copilot]

When all incoming science packets are in-flight calibration data (esa_table_num != 0), swe_l1b_science returns None (no complete 4-quarter cycles). swe_l1b was unconditionally appending this None to processed_datasets, causing downstream failures in post-processing.

Changes

• swe/l1b/swe_l1b.py: Guard the append in swe_l1b with a None check:

  # Before
  science_dataset = swe_l1b_science(dependencies)
  processed_datasets.append(science_dataset)  # silently appends None
  
  # After
  science_dataset = swe_l1b_science(dependencies)
  if science_dataset is not None:
      processed_datasets.append(science_dataset)

• tests/swe/test_swe_l1b.py: Add test_swe_l1b_no_full_cycles — mocks swe_l1b_science returning None and asserts the returned dataset list contains no None entries.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• api.dev.imap-mission.com
  • Triggering command: /usr/bin/python python -m pytest imap_processing/tests/swe/test_swe_l1b.py::test_swe_l1b_no_full_cycles -v (dns block)
  • Triggering command: /usr/bin/python python -m pytest imap_processing/tests/swe/test_swe_l1b.py::test_get_full_cycle_data_indices imap_processing/tests/swe/test_swe_l1b.py::test_count_rate imap_processing/tests/swe/test_swe_l1b.py::test_get_checker_board_pattern -v -m (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>SWE L1b failure</issue_title>
<issue_description>In the latest SWE l1b job, there is an unbound local error during processing.

Processing SWE l1b
Traceback (most recent call last):
  File "/usr/local/bin/imap_cli", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 1523, in main
    instrument.process()
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 444, in process
    products = self.do_processing(dependencies)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 1378, in do_processing
    datasets = swe_l1b(dependencies)
               ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/swe/l1b/swe_l1b.py", line 954, in swe_l1b
    science_dataset = swe_l1b_science(dependencies)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/swe/l1b/swe_l1b.py", line 739, in swe_l1b_science
    full_cycle_l1a_data, checkerboard_pattern
    ^^^^^^^^^^^^^^^^^^^
UnboundLocalError: cannot access local variable 'full_cycle_l1a_data' where it is not associated with a value
```</issue_description>

<agent_instructions>Processing SWE l1b
Traceback (most recent call last):
  File "/usr/local/bin/imap_cli", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 1523, in main
    instrument.process()
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 444, in process
    products = self.do_processing(dependencies)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/cli.py", line 1378, in do_processing
    datasets = swe_l1b(dependencies)
               ^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/swe/l1b/swe_l1b.py", line 954, in swe_l1b
    science_dataset = swe_l1b_science(dependencies)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/imap_processing/swe/l1b/swe_l1b.py", line 739, in swe_l1b_science
    full_cycle_l1a_data, checkerboard_pattern
    ^^^^^^^^^^^^^^^^^^^
UnboundLocalError: cannot access local variable 'full_cycle_l1a_data' where it is not associated with a value</agent_instructions>

## Comments on the Issue (you are @copilot in this section)

<comments>
</comments>

• Fixes SWE L1b failure #2425

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.