feat(tvix/nar-bridge): support uploading NAR files

This ingests NAR files into the {Blob,Directory}Service, which are
already part of the AppState.

As we then need to correlate the root node to the uploaded PathInfo, we
need to keep a (short-lived) lookup table from NARHash to root node
around. We insert it into a `LruCache` after the NAR is uploaded, and
use `peek()` to do the lookup, which doesn't update the LRU list.

Change-Id: I48a4c6246bacf76559c5a4ccad2a0bc25c1b7900
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11986
Tested-by: BuildkiteCI
Reviewed-by: Brian Olsen <me@griff.name>

tvix/Cargo.lock

@@ -2246,9 +2246,12 @@ dependencies = [
  "bytes",
  "clap",
  "data-encoding",
+ "futures",
  "hex-literal",
  "itertools 0.12.0",
+ "lru",
  "nix-compat",
+ "parking_lot 0.12.3",
  "prost",
  "prost-build",
  "rstest",
@@ -2436,7 +2439,7 @@ dependencies = [
  "hyper 0.14.28",
  "itertools 0.12.0",
  "md-5",
- "parking_lot 0.12.2",
+ "parking_lot 0.12.3",
  "percent-encoding",
  "quick-xml",
  "rand",
@@ -2599,9 +2602,9 @@ dependencies = [
 
 [[package]]
 name = "parking_lot"
-version = "0.12.2"
+version = "0.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7e4af0ca4f6caed20e900d564c242b8e5d4903fdacf31d3daf527b66fe6f42fb"
+checksum = "f1bf18183cf54e8d6059647fc3063646a1801cf30896933ec2311622cc4b9a27"
 dependencies = [
  "lock_api",
  "parking_lot_core 0.9.9",
@@ -4542,7 +4545,7 @@ dependencies = [
  "lazy_static",
  "libc",
  "object_store",
- "parking_lot 0.12.2",
+ "parking_lot 0.12.3",
  "petgraph",
  "pin-project-lite",
  "prost",
@@ -4727,7 +4730,7 @@ dependencies = [
  "lazy_static",
  "lru",
  "nix-compat",
- "parking_lot 0.12.2",
+ "parking_lot 0.12.3",
  "pin-project-lite",
  "prost",
  "prost-build",