Better source-exclude reference docs (#16832)

Fixed https://github.com/astral-sh/uv/issues/16821

This is already explained in the guide, but it was missing from the
reference docs.

---------

Co-authored-by: Zanie Blue <contact@zanie.dev>

crates/uv-build-backend/src/settings.rs

@@ -70,6 +70,9 @@ pub struct BuildBackendSettings {
     pub default_excludes: bool,
 
     /// Glob expressions which files and directories to exclude from the source distribution.
+    ///
+    /// These exclusions are also applied to wheels to ensure that a wheel built from a source tree
+    /// is consistent with a wheel built from a source distribution.
     #[option(
         default = r#"[]"#,
         value_type = "list[str]",

docs/concepts/build-backend.md

@@ -230,7 +230,7 @@ From these,
 [`tool.uv.build-backend.source-exclude`](../reference/settings.md#build-backend_source-exclude),
 [`tool.uv.build-backend.wheel-exclude`](../reference/settings.md#build-backend_wheel-exclude) and
 the default excludes are removed. The source dist excludes are applied to avoid source tree to wheel
-source builds including more files than source tree to source distribution to wheel build.
+builds including more files than source tree to source distribution to wheel build.
 
 There are no specific wheel includes. There must only be one top level module, and all data files
 must either be under the module root or in the appropriate

uv.schema.json

@@ -744,7 +744,7 @@
           "default": false
         },
         "source-exclude": {
-          "description": "Glob expressions which files and directories to exclude from the source distribution.",
+          "description": "Glob expressions which files and directories to exclude from the source distribution.\n\nThese exclusions are also applied to wheels to ensure that a wheel built from a source tree\nis consistent with a wheel built from a source distribution.",
           "type": "array",
           "default": [],
           "items": {