feat(users/Profpatsch/whatcd-resolver): trace http requests

Move the http calls into their own module, so we can trace the request
and provide a simple copy-to-replay command.

We have to work around a bug in the otel library, which would limit
our attribute value length to 128 bytes because it uses the wrong
option value.

~~~

`ifExists` is finally made more useful for dealing with optional
attributes in e.g. lists.

Change-Id: Iafab523e9ec4b00136db43f31fdc12aeefb7f77c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11241
Tested-by: BuildkiteCI
Autosubmit: Profpatsch <mail@profpatsch.de>
Reviewed-by: Profpatsch <mail@profpatsch.de>

users/Profpatsch/whatcd-resolver/whatcd-resolver.cabal

@@ -66,6 +66,8 @@ library
        WhatcdResolver
        AppT
        JsonLd
+       Optional
+       Http
        Html
        Transmission
        Redacted
@@ -84,7 +86,9 @@ library
         aeson-better-errors,
         aeson,
         blaze-html,
+        blaze-markup,
         bytestring,
+        case-insensitive,
         containers,
         unordered-containers,
         directory,
@@ -95,12 +99,14 @@ library
         hs-opentelemetry-api,
         http-conduit,
         http-types,
+        http-client,
         ihp-hsx,
         monad-logger,
         mtl,
         network-uri,
         resource-pool,
         postgresql-simple,
+        punycode,
         scientific,
         selective,
         tmp-postgres,