Add rome_formatter fork as ruff_formatter (#2872)

The Ruff autoformatter is going to be based on an intermediate representation (IR) formatted via [Wadler's algorithm](https://homepages.inf.ed.ac.uk/wadler/papers/prettier/prettier.pdf). This is architecturally similar to [Rome](https://github.com/rome/tools), Prettier, [Skip](https://github.com/skiplang/skip/blob/master/src/tools/printer/printer.sk), and others.

This PR adds a fork of the `rome_formatter` crate from [Rome](https://github.com/rome/tools), renamed here to `ruff_formatter`, which provides generic definitions for a formatter IR as well as a generic IR printer. (We've also pulled in `rome_rowan`, `rome_text_size`, and `rome_text_edit`, though some of these will be removed in future PRs.)

Why fork? `rome_formatter` contains code that's specific to Rome's AST representation (e.g., it relies on a fork of rust-analyzer's `rowan`), and we'll likely want to support different abstractions and formatting capabilities (there are already a few changes coming in future PRs). Once we've dropped `ruff_rowan` and trimmed down `ruff_formatter` to the code we currently need, it's also not a huge surface area to maintain and update.

crates/ruff_text_size/src/serde_impls.rs

@@ -0,0 +1,48 @@
+use {
+    crate::{TextRange, TextSize},
+    serde::{de, Deserialize, Deserializer, Serialize, Serializer},
+};
+
+impl Serialize for TextSize {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        self.raw.serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for TextSize {
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        u32::deserialize(deserializer).map(TextSize::from)
+    }
+}
+
+impl Serialize for TextRange {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        (self.start(), self.end()).serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for TextRange {
+    #[allow(clippy::nonminimal_bool)]
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        let (start, end) = Deserialize::deserialize(deserializer)?;
+        if !(start <= end) {
+            return Err(de::Error::custom(format!(
+                "invalid range: {:?}..{:?}",
+                start, end
+            )));
+        }
+        Ok(TextRange::new(start, end))
+    }
+}