fix: when 'data' is nil, panic occurs

[Luoxin]

No description provided.

[Skyxim]

mihomo/common/structure/structure.go

Line 74 in f020b20

if !ok || value == nil {

It has been ensured that the decode input parameter data is not nil. Is there a clear location that causes panic?
Could you add a unit test?

[Luoxin]

mihomo/common/structure/structure.go

Line 251 in f020b20

name, val.Type(), dataVal.Type(),

The location where the panic occurred is /common/structure/structure.go:251. The error reported at that time was because dataVal was Zero, which caused the dataValue.Type() call in the default branch to throw panic. The original error message is

panic: reflect: call of reflect.Value.Type on zero Value

After searching, it was found that the value of h2-opts.path in the configuration was set to nil. The original source of the configuration is not yet known. Related unit tests have been added.

[Skyxim]

After searching, it was found that the value of h2-opts.path in the configuration was set to nil.

It seems that the value in the map is not checked. Just add the check here.

mihomo/common/structure/structure.go

Line 370 in f020b20

if err := d.decode(fieldName, k.Interface(), currentKey); err != nil {