[ENH] Upgrade to foyer 0.20.1 to support multi-disk (#5887)

## Description of changes

_Summarize the changes made by this PR._

- Improvements / New functionality
  - Supports multi disk configuration on foyer. 
  - Derived from #5877 but notable improvements: 
1. Actually tests the new behavior and adds logic to make it work in the
various parsing configurations.
2. Adds .with_direct() flag to match previous behavior. This was missed
in #5877
3. Adds support for clap parsing an empty default value, this ensures
memory cache which does not need this argument can be created without
needing to be specified. clap(skip) has the same behavior but this is
more explicit and thus preferred. The string parsing should tolerate
empty paths, whitespaces other misc formatting issues.
       4. More helpful and descriptive error messages
5. Supports the legacy capacity: case since we now flatten capacity into
the root. And adds tests for this
  - Read through foyer implementation to confirm no other regressions.

## Test plan

_How are these changes tested?_
I have test legacy config, clap parsing of new config, the new multi
disk config with single disks, and the config with multiple disks.
- [x] Tests pass locally with `pytest` for python, `yarn test` for js,
`cargo test` for rust

## Migration plan
No migration should be required since we handle the legacy case.

## Observability plan
None

## Documentation Changes
None

---------

Co-authored-by: Max Isom <[email protected]>

Author: HammadB

Cargo.lock

@@ -8,8 +8,8 @@ path = "src/lib.rs"
 
 [dependencies]
 clap = { workspace = true }
-foyer = { version = "0.17.3", features = ["tracing", "serde"] }
-mixtrics = { version = "0.1.0", features = ["opentelemetry_0_27"] }
+foyer = { version = "0.20.1", features = ["tracing", "serde"] }
+mixtrics = { version = "0.2.3", features = ["opentelemetry_0_27"] }
 anyhow = "1.0"
 opentelemetry = { version = "0.27.0", default-features = false, features = ["trace", "metrics"] }
 

rust/cache/Cargo.toml

@@ -6,7 +6,7 @@ use chroma_cache::{CacheConfig, FoyerCacheConfig};
 
 fn main() {
     let config = FoyerCacheConfig::parse();
-    if config.dir.is_none() {
+    if config.disks().is_empty() {
         panic!("Disk cache is required for disk cache config writer");
     }
     let out = serde_yaml::to_string(&CacheConfig::Disk(config)).unwrap();

rust/cache/src/bin/cops-disk-cache-config-writer.rs

@@ -2,11 +2,11 @@
 
 use clap::Parser;
 
-use chroma_cache::{CacheConfig, FoyerCacheConfig};
+use chroma_cache::{CacheConfig, DiskFieldValue, FoyerCacheConfig};
 
 fn main() {
     let mut config = FoyerCacheConfig::parse();
-    config.dir = None;
+    config.disk = DiskFieldValue::MultiDisk(vec![]);
     let out = serde_yaml::to_string(&CacheConfig::Memory(config)).unwrap();
     print!("{out}");
 }