Report Python versions in pyvenv.cfg version mismatch (#13027)

When working on #13025 I noticed this message was lacking versions,
which seems frustrating if you're debugging things.

I refactored the general `matches_interpreter` utilities that were added
in https://github.com/astral-sh/uv/pull/12884 into a more purpose-fit
function that returns an `Option` with the versions if there's a
mismatch.

crates/uv-python/src/interpreter.rs

@@ -318,31 +318,37 @@ impl Interpreter {
         &self.markers.python_full_version().version
     }
 
-    /// Returns the full minor Python version.
+    /// Returns the Python version up to the minor component.
     #[inline]
     pub fn python_minor_version(&self) -> Version {
         Version::new(self.python_version().release().iter().take(2).copied())
     }
 
-    /// Return the major version of this Python version.
+    /// Returns the Python version up to the patch component.
+    #[inline]
+    pub fn python_patch_version(&self) -> Version {
+        Version::new(self.python_version().release().iter().take(3).copied())
+    }
+
+    /// Return the major version component of this Python version.
     pub fn python_major(&self) -> u8 {
         let major = self.markers.python_full_version().version.release()[0];
         u8::try_from(major).expect("invalid major version")
     }
 
-    /// Return the minor version of this Python version.
+    /// Return the minor version component of this Python version.
     pub fn python_minor(&self) -> u8 {
         let minor = self.markers.python_full_version().version.release()[1];
         u8::try_from(minor).expect("invalid minor version")
     }
 
-    /// Return the patch version of this Python version.
+    /// Return the patch version component of this Python version.
     pub fn python_patch(&self) -> u8 {
         let minor = self.markers.python_full_version().version.release()[2];
         u8::try_from(minor).expect("invalid patch version")
     }
 
-    /// Returns the Python version as a simple tuple.
+    /// Returns the Python version as a simple tuple, e.g., `(3, 12)`.
     pub fn python_tuple(&self) -> (u8, u8) {
         (self.python_major(), self.python_minor())
     }