* fix: promote matched tools from deferred registry after tool_search returns schema
After tool_search returns a tool's full schema, the tool is promoted
(removed from the deferred registry) so DeferredToolFilterMiddleware
stops filtering it from bind_tools on subsequent LLM calls.
Without this, deferred tools are permanently filtered — the LLM gets
the schema from tool_search but can never invoke the tool because
the middleware keeps stripping it.
Fixes#1554
* test: add promote() and tool_search promotion tests
Tests cover:
- promote removes tools from registry
- promote nonexistent/empty is no-op
- search returns nothing after promote
- middleware passes promoted tools through
- tool_search auto-promotes matched tools (select + keyword)
* fix: address review — lint blank line + empty registry guard
- Add missing blank line between FakeRequest methods (E301)
- Use 'if not registry' to handle empty registries consistently
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Co-authored-by: d 🔹 <258577966+voidborne-d@users.noreply.github.com>
Co-authored-by: Willem Jiang <willem.jiang@gmail.com>