fix(callbacks): wrap plug and phoenix callbacks

[solnic]

Now the callbacks reachable from a web request - remote_address_reader, the PlugContext scrubbers (body_scrubber, header_scrubber, cookie_scrubber, url_scrubber) and the PlugCapture / LiveViewHook scrubber - run through Sentry.Callback. A crash is logged as an error with :sentry log domain and the SDK falls back to its own default scrubbing, so the request is served as if nothing happened.

Two specific fixes on top of the wrapping: while capturing, a failure inside Sentry never replaces the application's own exception — the original one keeps propagating unchanged, and the LiveView hook scrubber falls back to empty data instead of raising, since raising in a hook takes down the LiveView process.

A scrubber that returns the wrong type now falls back to the default scrubber and is logged as a warning. Previously PlugCapture and LiveViewHook raised on a bad return value, so it was reported as a crash with a stacktrace, while the equivalent PlugContext case was a warning — they all report it the same way now.

[sentry]

Bug: An invalid :remote_address_reader option for Sentry.PlugContext causes an uncaught ArgumentError, crashing the request despite documentation promising that callback failures are handled.
_{Severity: MEDIUM}

Suggested Fix

Ensure that exceptions raised during callback preparation are also caught. This could be achieved by moving the Sentry.Callback.to_fun/3 call inside the Sentry.Callback.run/2 function or by wrapping the call in plug_context.ex with a try/rescue block to handle potential ArgumentError exceptions gracefully, thus upholding the documented guarantee.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: lib/sentry/live_view_hook.ex#L89

Potential issue: If an invalid value is provided for the `:remote_address_reader` option
in `Sentry.PlugContext` (e.g., a string or atom instead of a function or tuple), the
call to `Sentry.Callback.to_fun/3` will raise an `ArgumentError`. This exception is not
caught because it occurs before `Sentry.Callback.run/2` is invoked, which is intended to
handle callback failures. This behavior contradicts the documentation's promise that
callback failures will not affect the request, leading to an uncaught exception that
crashes the request process upon misconfiguration.

Also affects:

• lib/sentry/live_view_hook.ex:150~150

_{Did we get this right? 👍 / 👎 to inform future reviews.}