refactor: split pod metadata store

crates/pod-store/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "pod-store"
+description = "Durable Pod-name metadata/state persistence"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+
+[dependencies]
+session-store = { workspace = true }
+serde = { workspace = true, features = ["derive"] }
+serde_json = { workspace = true }
+thiserror = { workspace = true }
+
+[dev-dependencies]
+tempfile = { workspace = true }