[ty] Add search paths info to unresolved import diagnostics (#20040)

Fixes https://github.com/astral-sh/ty/issues/457

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Co-authored-by: Alex Waygood <alex.waygood@gmail.com>

crates/ty_python_semantic/src/module_resolver/mod.rs

@@ -10,8 +10,7 @@ pub use resolver::{resolve_module, resolve_real_module};
 use ruff_db::system::SystemPath;
 
 use crate::Db;
-use crate::module_resolver::resolver::{ModuleResolveMode, search_paths};
-use resolver::SearchPathIterator;
+pub(crate) use resolver::{ModuleResolveMode, SearchPathIterator, search_paths};
 
 mod list;
 mod module;