✨➕ vanth, workspace: Add entity ID system and serialization dependencies

- Added new modules `entity` and `store` to `vanth` crate for ECS foundations
- Implemented generic `Id` type with serialization/deserialization support
- Introduced `serde` and `serde_json` dependencies in workspace and vanth crate
- Defined `Vanth` struct and `ContentHash` component in `lib.rs`
- Added placeholder `Store` component in new module
- Updated workspace configuration with `resolver = "3"` and dependency versions

Cargo.toml

@@ -1,6 +1,13 @@
 [workspace]
 members = ["crates/*"]
+resolver = "3"
+
+[workspace.package]
+version = "0.1.0"
+edition = "2024"
 
 [workspace.dependencies]
 bevy_app = "0.16.1"
 bevy_ecs = "0.16.1"
+serde = { version = "1.0.219", features = ["derive"] }
+serde_json = "1.0.140"