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/shell.nix

@@ -56,6 +56,7 @@ pkgs.mkShell {
       h.resource-pool
       h.xmonad-contrib
       h.hs-opentelemetry-sdk
+      h.punycode
     ]))
 
     pkgs.rustup