[ty] Make Module a Salsa ingredient

We want to write queries that depend on `Module` for caching. While it
seems it can be done without making `Module` an ingredient, it seems it
is best practice to do so.

[best practice to do so]: https://github.com/astral-sh/ruff/pull/19408#discussion_r2215867301

crates/ty_python_semantic/src/semantic_index/builder.rs

@@ -1278,7 +1278,7 @@ impl<'ast> Visitor<'ast> for SemanticIndexBuilder<'_, 'ast> {
                             continue;
                         };
 
-                        let Some(referenced_module) = module.file() else {
+                        let Some(referenced_module) = module.file(self.db) else {
                             continue;
                         };