ltspice://symbols, ltspice://examples, ltspice://status raised TypeError on
read -- they called list_symbols/list_examples/check_installation, which are
@mcp.tool() FunctionTool objects (not callable). Split those three into plain
*_impl functions + thin tool wrappers, and point the resources at the impls.
The other library tools move verbatim.
Adds test_resources.py to read every resource (regression guard). Library tool
outputs verified byte-identical old-vs-new. server.py: 2168 -> 1876 lines.