Put and Read: content on the socket, for clients that share no files

The system daemon runs as its own user behind ProtectHome, so it can
neither read a file a desktop app wrote for Add nor write one back for
Materialize - redoal on the system varde failed every get with EACCES.
Put imports base64 bytes carried in the request and Read returns a raw
blob's bytes in the reply, both up to MAX_INLINE_BYTES (16 MiB).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

varde-ctl/src/main.rs

@@ -246,6 +246,7 @@ fn print_human(data: Option<&ResponseData>) {
     match data {
         ResponseData::Added { hash, bytes } => println!("added {hash} ({bytes} bytes)"),
         ResponseData::Pinned { hash } => println!("pinned {hash}"),
+        ResponseData::Bytes { data } => println!("{data}"),
         ResponseData::Done {} => println!("ok"),
         ResponseData::Materialized { bytes, reflinked } => {
             let how = if *reflinked { "reflinked" } else { "copied" };