[GR-59419] Implement compact constant pools.

[graalvmbot]

This PR implements compact constant pools which are shared by both Espresso and Crema.
It reduces the footprint of the .class metadata by avoiding wrapper objects for every CP entry, it saves ~6MB from the default libjavavm.so . It also removes a net ~1300 lines of code.

On AWFY, there's a 2.4% interpreter speedup and 7.6% RSS savings, note that metadata footprint is reduced by a larger factor, but it only accounts for a relatively small part of the RSS compared to Truffle/compiler and the memory used by applications.

Some history
The constant pool was introduced in the very first Espresso commit, by Doug, based on Maxine. At the time, the footprint of the metadata was already a concern, but we couldn't really measure it, so we postponed any (deemed premature) optimizations. This PR finally tackles the longstanding CP metadata overhead.

Main changes
PoolConstant and all its sub-classes are removed, the new CP provides methods to retrieve the metadata for every constant type. With the new design instead of passing PoolConstants around, you must pass ConstantPool + cpi instead.
I tried to avoid exposing the indices as much as I could e.g. Symbol<Name> name = cp.className(classIndex) instead of int nameIndex = cp.classNameIndex(classIndex);

Additional metadata savings
I did some further cleanups like reducing the footprint of attributes, removed LinkedMethod and purged the UtfConstantTable.

The PR is somehow disruptive, to make the review easier:
The Espresso JVMCI implementation uses RuntimeConstantPool#peekResolvedOrNull instead,
Thomas: this PR touches the verifier; the changes are minimal and it really helped that the verifier works mostly with the ImmutableConstantPool.
Allan: there are some minor changes in redefinition, in some places I had to obtain the CP from the declaring class and NOT from the MethodVersion.