[DBX-82245] implement LH getPDF for 526 backup path

[SamStuckey]

Summary

Adds the ability to submit backup submissions using PDFs generated by the correct Service based on initial submission path.

• *This work is behind a feature toggle (flipper): * Indirectly Yes
• Adding conditional path based on if claim was submitted to claims_api (instead of EVSS). In new path, PDFs will be generated using appropriate API
• Disability

Related issue(s)

• #82245

Testing done

• New code is covered by unit tests
• PDFs always generated using EVSS, now they are generated by which endpoint the primary submission would have used
• Generate Lighthouse claim, trigger backup submission using code:

sub = <your Form526Submission>
processor = Sidekiq::Form526BackupSubmissionProcess::Processor.new(sub.id, get_upload_location_on_instantiation: false)
processor.process!

then fetch the claim from Benefits Intake API

• If this work is behind a flipper:
  • Tests need to be written for both the flipper on and flipper off scenarios. Docs.
  • This path is part of the backup submission process. It will be monitored closely and coordinated with OBI to ensure proper resolution of submission

Screenshots

Note: Optional

What areas of the site does it impact?

(Describe what parts of the site are impacted andifcode touched other areas)

Acceptance criteria

• I fixed|updated|added unit tests and integration tests for each feature (if applicable).
• No error nor warning in the console.
• Events are being sent to the appropriate logging solution
• Documentation has been updated (link to documentation)
• No sensitive information (i.e. PII/credentials/internal URLs/etc.) is captured in logging, hardcoded, or specs
• Feature/bug has a monitor built into Datadog or Grafana (if applicable)
• If app impacted requires authentication, did you login to a local build and verify all authenticated routes work as expected
• I added a screenshot of the developed feature

Requested Feedback

(OPTIONAL)What should the reviewers know in addition to the above. Is there anything specific you wish the reviewer to assist with. Do you have any concerns with this PR, why?

[freeheeling]

lgtm