feat(tvix/store): add redb PathInfoService

This provides a PathInfoService implementation using redb
(https://github.com/cberner/redb) as the underlying storage engine.

Both an in-memory variant, as well as a filesystem one is provided,
similar how it's done with the sled implementation.

Supersedes: https://cl.tvl.fyi/c/depot/+/11692
Change-Id: I744619c51bf2efd0fb63659b12a27cbe0b2fd6fc
Signed-off-by: Ilan Joselevich <personal@ilanjoselevich.com>
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11995
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI

tvix/Cargo.lock

@@ -3209,6 +3209,15 @@ dependencies = [
  "crossbeam-utils",
 ]
 
+[[package]]
+name = "redb"
+version = "2.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a6dd20d3cdeb9c7d2366a0b16b93b35b75aec15309fbeb7ce477138c9f68c8c0"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.2.16"
@@ -4808,6 +4817,7 @@ dependencies = [
  "pin-project-lite",
  "prost 0.13.1",
  "prost-build 0.13.1",
+ "redb",
  "rstest",
  "rstest_reuse",
  "serde",
@@ -4994,6 +5004,7 @@ dependencies = [
  "pin-project-lite",
  "prost 0.13.1",
  "prost-build 0.13.1",
+ "redb",
  "reqwest",
  "reqwest-middleware",
  "rstest",