✨➖📝 cli, vanth, meta, flake: Simplify dependencies, add meta crate, and improve docs

- Removed dependencies `sqlx` and `bevy_app` to simplify the project.
- Added new crate `vanth_meta` for generating example SVGs.
- Updated CLI tests to use `assert_cmd` for better test assertions.
- Enhanced README with comprehensive library and CLI usage documentation.
- Modified `Store::write` in `vanth` crate to return the content hash.
- Set `checkPhase` to empty in Nix flake configuration.

Cargo.toml

@@ -6,9 +6,11 @@ resolver = "3"
 version = "0.1.0"
 edition = "2024"
 
+[workspace.metadata.crane]
+name = "vanth"
+
 [workspace.dependencies]
 clap = { version = "4.5.42", features = ["derive"] }
-bevy_app = "0.16.1"
 bevy_ecs = "0.16.1"
 bincode = "2.0.1"
 serde = { version = "1.0.219", features = ["derive"] }
@@ -18,10 +20,10 @@ blake3 = { version = "1.8.2", features = ["traits-preview"] }
 quote = "1.0"
 syn = { version = "2.0", features = ["full"] }
 proc-macro2 = "1.0"
-sqlx = "0.8.6"
 rusqlite = { version = "0.32.1", features = ["bundled"] }
 tempfile = "3.12.0"
 rand_core = "0.6.4"
 rand_chacha = { version = "0.3.1", features = ["serde1"] }
 tracing = "0.1.41"
 tracing-subscriber = "0.3.19"
+assert_cmd = "2.0.17"