Tweak valence_nbt (#430)

# Objective

- Fix a few small things before releasing 0.5. For #428 

# Solution

- Remove redundant `element_type` method from `Tag`.
- `get_tag` -> `tag`.
- Remove macro generated methods from `Value`.
- Create `From<Value> for List` impl which creates a new singleton list.
- Clean up snbt code a bit.

crates/valence_nbt/Cargo.toml

@@ -10,6 +10,7 @@ version = "0.5.0"
 edition.workspace = true
 
 [features]
+default = ["snbt"] # TODO: remove me
 binary = ["dep:byteorder", "dep:cesu8"]
 snbt = []
 # When enabled, the order of fields in compounds are preserved.

crates/valence_nbt/src/binary/decode.rs

@@ -247,7 +247,7 @@ impl<W: Write> EncodeState<W> {
 
     fn write_compound(&mut self, c: &Compound) -> Result<()> {
         for (k, v) in c.iter() {
-            self.write_tag(Tag::element_type(v))?;
+            self.write_tag(v.tag())?;
             self.write_string(k)?;
             self.write_value(v)?;
         }