slang-server hover width is per-declaration: trust it for parameterized ports only when getInstances returns exactly one instance

When an editor or waveform tool maps a SystemVerilog net to the ports it connects (an alias for nets the simulator didn't dump), it needs the declaration's width. slang-server's hover on a declaration like logic [N-1:0] x shows Type: logic[0:0] for ONE elaboration only. If the module is instantiated several times with different parameters, every instance gets that same width. Safe rule: accept the literal range or a package typedef width directly. Otherwise accept the hover's resolved width only when the server's getInstances on that declaration returns exactly one hierarchical path. Replicated generate blocks and multi-instance modules return several paths and stay conservative. A declaration directly in an elaborated top counts as one instance, even in an included fragment where getInstances returns []. Make a getInstances timeout throw, not count as one.