log more info in PUT/GET requests to help with debugging

[samlaf]

We often want access to more info related to GET/PUT requests, to help with debugging. 2 main ones right now are:

1. blob size
2. blob header hash (to be able to trace request in eigenda backend, which keys requests by the blobHeaderHash, aka BlobKey)

Right now our logs only log the commitment:

[da-server-op-kurtosis] Apr 16 10:15:05.324 INF server/middleware.go:96 request method=GET url=/get/0x010001f9019af9013df8b6f88080820001f859f842a0249d7dab4031f28b3f9b4db036f713a0509bfa12a622fea52abe7236bd47b907a0238c9a06fc85a9cf22dc177aa3c20909f646897517dd11a08231649b23eaa6c2ccc4128202dac682034d8202f6c6c28080c2808004a0a37cd432ac2a212e1e0ed8f967a09653ee0357f6f1be2054e4bfddc8c3e5fa02b0db595374202dcfe47b28536ce93aabefb9620a9aed4da85dd7c1a2ee02173a08f78a0c462e0086e16badc91de1cca696c20b1c8201cab880a3a7e2db402ef44298bc5b6442c2011d36717be063d078daf6ac4d4a49977a6004ad6b0545d94ad73e986d4f5a1af2c5972486ec2c49606c7172e22763cd35e929715754bd3c8754f9bb2c5a0118b892987a03f7eaad05dd1ec69ab45ee41aa574ac8c4ac7b7c375539f2e51a31f0a2a69c039d03f29addc11576a6761d2d339e2a0397754f7612b72a79533520d3498426eb6227c552cdb126481147fc814d0f8ad05f5c2041fc5c482032617c7c682016a820113cec68201ae8213e7c68201e6820335c68202bb82026cc21a13c30b1f10c6c2080ac2090c80 status=200 duration=1.0675ms

We should add more key-value pairs for other information we need to consume.