Fix breaking references after GC.compact

[ksss]

Although rare, there's a possibility of breaking references after GC.compact if a dynamic symbol happens to be interned into the constant pool.
To fix this issue, I've modified the code to copy the string and intern it as an owned type when a dynamic symbol is passed.
Additionally, we've written a test case that reproduces the problem.

[ksss]

I found that even static symbols can have broken references starting from 4.0, so I fixed it to copy uniquely.