Add [tool.uv.dependency-groups].mygroup.requires-python (#13735)

This allows you to specify requires-python on individual dependency-groups,
with the intended usecase being "oh my dev-dependencies have a higher
requires-python than my actual project".

This includes a large driveby move of the RequiresPython type to
uv-distribution-types to allow us to generate the appropriate markers at
this point in the code. It also migrates RequiresPython from
pubgrub::Range to version_ranges::Ranges, and makes several pub(crate)
items pub, as it's no longer defined in uv_resolver.

Fixes #11606

crates/uv-configuration/src/dependency_groups.rs

@@ -295,6 +295,15 @@ pub struct DependencyGroupsWithDefaults {
 }
 
 impl DependencyGroupsWithDefaults {
+    /// Do not enable any groups
+    ///
+    /// Many places in the code need to know what dependency-groups are active,
+    /// but various commands or subsystems never enable any dependency-groups,
+    /// in which case they want this.
+    pub fn none() -> Self {
+        DependencyGroups::default().with_defaults(DefaultGroups::default())
+    }
+
     /// Returns `true` if the specification was enabled, and *only* because it was a default
     pub fn contains_because_default(&self, group: &GroupName) -> bool {
         self.cur.contains(group) && !self.prev.contains(group)

crates/uv-configuration/src/extras.rs

@@ -263,6 +263,14 @@ pub struct ExtrasSpecificationWithDefaults {
 }
 
 impl ExtrasSpecificationWithDefaults {
+    /// Do not enable any extras
+    ///
+    /// Many places in the code need to know what extras are active,
+    /// but various commands or subsystems never enable any extras,
+    /// in which case they want this.
+    pub fn none() -> Self {
+        ExtrasSpecification::default().with_defaults(DefaultExtras::default())
+    }
     /// Returns `true` if the specification was enabled, and *only* because it was a default
     pub fn contains_because_default(&self, extra: &ExtraName) -> bool {
         self.cur.contains(extra) && !self.prev.contains(extra)