Locks in the exact-match semantics that distinguish resolve_index from
get_variable, so the lookup used by tune_circuit and plot_waveform is now
covered without needing the live LTspice path.
Rename package from mcp-ltspice/mcp_ltspice to mcltspice throughout:
source directory, imports, pyproject.toml, tests, and README.
Remove startup banner prints from main() since FastMCP handles
its own banner and stdout is the MCP JSON-RPC transport.
Point repo URL at git.supported.systems/MCP/mcltspice.
