deps/vm: vendor regress 0.11.1 补 Script/Script_Extensions 的 Unknown(Zzzz) 取值——上游表缺未分配码点集取值，规范合法模式 \p{Script=Unknown} 编译期 SyntaxError；fork 纯增量（0 行改动上游行，仅补区间表与解析臂），回归钉四则（未分配匹配/已分配不匹配/sc·scx·Zzzz 别名/既有取值不扰动）

third_party/regress/src/exec.rs

@@ -0,0 +1,56 @@
+//! Execution engine bits.
+
+use crate::api::Match;
+use crate::insn::CompiledRegex;
+use crate::position::PositionType;
+
+/// A trait for finding the next match in a regex.
+/// This is broken out from Executor to avoid needing to thread lifetimes
+/// around.
+pub trait MatchProducer: core::fmt::Debug {
+    /// The position type of our indexer.
+    type Position: PositionType;
+
+    /// \return an initial position for the given start offset.
+    fn initial_position(&self, offset: usize) -> Option<Self::Position>;
+
+    /// Attempt to match at the given location.
+    /// \return either the Match and the position to start looking for the next
+    /// match, or None on failure.
+    fn next_match(
+        &mut self,
+        pos: Self::Position,
+        next_start: &mut Option<Self::Position>,
+    ) -> Option<Match>;
+}
+
+/// A trait for executing a regex.
+pub trait Executor<'r, 't>: MatchProducer {
+    /// The ASCII variant.
+    type AsAscii: Executor<'r, 't>;
+
+    /// Construct a new Executor.
+    fn new(re: &'r CompiledRegex, text: &'t str) -> Self;
+}
+
+/// A struct which enables iteration over matches.
+#[derive(Debug)]
+pub struct Matches<Producer: MatchProducer> {
+    mp: Producer,
+    position: Option<Producer::Position>,
+}
+
+impl<Producer: MatchProducer> Matches<Producer> {
+    pub fn new(mp: Producer, start: usize) -> Self {
+        let position = mp.initial_position(start);
+        Matches { mp, position }
+    }
+}
+
+impl<Producer: MatchProducer> Iterator for Matches<Producer> {
+    type Item = Match;
+    fn next(&mut self) -> Option<Self::Item> {
+        let pos = self.position?;
+        self.mp.next_match(pos, &mut self.position)
+    }
+}