Log canceled challenge lookups at DEBUG

[danillouz]

Follow-up of: #8

A big chunk of the noisy "looking up info for HTTP challenge" logs are "context canceled": https://onenr.io/0VjY3rN1qw0

So also log these as DEBUG, but only do so when both the lookup error and HTTP request context are canceled.

[Copilot]

Pull request overview

Adjusts HTTP challenge lookup logging to reduce noise by treating expected cancellation scenarios as DEBUG when both the storage lookup error and the request context indicate cancellation, aligning with prior work to de-noise challenge lookup logs.

Changes:

• Downgrade “looking up info for HTTP challenge” logs to DEBUG when both the lookup error and request context are context.Canceled.
• Extend unit tests to cover canceled-request vs canceled-storage behaviors and validate resulting log levels.
• Wrap distributed challenge token file load errors with %w so errors.Is(..., context.Canceled) works through wrapping.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
httphandlers.go	Logs canceled HTTP challenge lookups at DEBUG when both the storage error and request context are canceled.
httphandlers_test.go	Adds test cases ensuring canceled requests log at DEBUG while storage-only cancellations remain WARN.
config.go	Switches to %w wrapping for distributed token file open errors to preserve underlying error identity for errors.Is.

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[ankon]

LGTM, same as with #8: This should be upstreamed (make a PR against caddy/certmagic), and then link these.

This will make future updates easier.

[danillouz]

LGTM, same as with #8: This should be upstreamed (make a PR against caddy/certmagic), and then link these.

This will make future updates easier.

Good one, I also flagged it here: https://framer-team.slack.com/archives/C06505JMQK0/p1783883343394879?thread_ts=1741345255.812599&cid=C06505JMQK0

Will deploy this first, then if Matt is okay with it, will upstream it

[danillouz]

As per: https://github.com/framer/FramerDomainsServer/#upgrading-certmagic

This needs to become a "fork revision" after merging: v0.25.3-framer.2

And a corresponding FDS PR to use that