[#709] Fix error handling in morley-client

Description

Problem: There's a bug in handleOperationResult that might throw away useful information about the error reason.

Solution: Rewrite it. Also remove redundant combineResults. The trick is to collect all RunErrors and AppliedResults in the first pass, making note of whether we encountered OperationFailed at least once. If we did, handle the list of RunErrors. If we didn't, return the list of AppliedResults. This is somewhat complicated by the fact that we merge AppliedResults within one operation, but not between operations.

Related issue(s)

Resolves #709 (closed), supersedes !1086 (closed)

Checklist for your Merge Request

Related changes (conditional)

• Tests (see short guidelines)

  • If I added new functionality, I added tests covering it.
  • If I fixed a bug, I added a regression test to prevent the bug from silently reappearing again.

• Documentation

  • I checked whether I should update the docs and did so if necessary:
    • Root README and other README.md files
    • Haddock
    • docs/
  • I updated changelog files of all affected packages released to Hackage if my changes are externally visible.

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assigned to @lierdakil

mentioned in merge request !1086 (closed)

requested review from @diogo.castro and @pasqu4le

added 1 commit

• 964f48bb - [#709 (closed)] Fix error handling in morley-client

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added 1 commit

• 9103f335 - [#709 (closed)] Fix error handling in morley-client

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added 1 commit

• 3c688055 - [#709 (closed)] Fix error handling in morley-client

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approved this merge request

approved this merge request

added 29 commits

• 3c688055...a7fad974 - 27 commits from branch master
• e7c84382 - [#709 (closed)] Fix error handling in morley-client
• 632e6ea7 - [Chore] Update changelog

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approved this merge request

enabled an automatic merge when the pipeline for 632e6ea7 succeeds

aborted the automatic merge because target branch was updated

added 20 commits

• 632e6ea7...c23bee2b - 18 commits from branch master
• 98223a69 - [#709 (closed)] Fix error handling in morley-client
• 2122c3e6 - [Chore] Update changelog

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enabled an automatic merge when the pipeline for 2122c3e6 succeeds

mentioned in commit 17b42016

merged