tor-persist: Big refactoring on Error type.

Every error now has an action (what we were trying to do), a resource (what we were trying to do it to), and a source (what problem we encountered).

Initially I tried to add "action" and "resource" fields to error variants individually, but that led to a combinatorial explosion.

Part of #323 (closed).

assigned to @nickm

requested review from @eta

approved this merge request

enabled an automatic merge when the pipeline for 8cea3f73 succeeds

lgtm! (retrying spurious pipeline failure)

canceled the automatic merge

added 8 commits

• 8cea3f73...372ff615 - 6 commits from branch tpo/core:main
• aeef36a5 - tor-persist: Move Error to a module.
• 6e36693a - tor-persist: Big refactoring on Error type.

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enabled an automatic merge when the pipeline for 6e36693a succeeds

(rebasing on main to fix rustsec)

Adding a new fixup commit, then squashing, to try to fix minimal-versions

added 1 commit

• 862bfae7 - fixup! tor-persist: Big refactoring on Error type.

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marked this merge request as draft from nickm/arti@862bfae7

added 1 commit

• 853aed68 - tor-persist: Big refactoring on Error type.

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Updated.

marked this merge request as ready

merged

mentioned in commit 0537e88d

mentioned in issue #177