Fixing a few issues with the soroban-sdk's production of specs (type ids, name collisions, aliasing, ...)

[leighmcculloch]

Hi all,

We're making a change to soroban-sdk that is largely an implementation detail, but I wanted to give some visibility to as it will eliminate a few problems that have existed since inception.

The change will make every type in contract specs uniquely identifiable. Spec entry names outputted by the soroban-sdk macros will change from being simple names like MyType to fully qualified paths ::mycrate::apath::MyType and then the stellar-cli will reduce them back to unique short identifiers.

Why:

• Eliminate name collisions in complex contracts / libraries #1570
• Make it possible to support type aliasing transparently #1857 #1063
• Optimise the data we need to store to perform spec shaking #1978

Why now:

• These have been issues that existed for a few years and have affected contract developers from time to time.
• Earlier this year we rewrote spec shaking because v1 wasn't scaling with larger libraries.
• While implementing spec shaking v2 we saw an opportunity to how to apply ideas we were exploring to the problems above.
• ⭐ AI tooling gave us the ability to explore and validate a few different solutions end-to-end.

Ecosystem Impact:

• None other than fixing incorrectly generated specs in cases described in the why above.
• This change is internal to the sdk<>cli build system and will be invisible to client SDKs, and tooling other than the stellar-cli.

These are the changes:

1️⃣ Change when contract specs are produced to later in the compilation process instead of at proc-macro expansion time. This provides the foundation for constructing the specs from information that is only known later in the compilation process, like the fully qualified name of a type:

• Add const XDR serialization rs-stellar-xdr#580
• Encode contract spec XDR at compile time rs-soroban-sdk#1965

2️⃣ Add fully qualified type names in contract specs and pre-process them:

• Widen contract spec type and event name limits stellar-xdr#312
• Widen contract spec type and event name limits rs-stellar-xdr#566
• Qualify type and event names rs-soroban-sdk#1970
• Reduce qualified type and event names stellar-cli#2674

3️⃣ Leverage the unique names to optimise the data that needs to be stored in contracts for spec shaking:

• Shake specs by reachability and markers rs-soroban-sdk#2043
• Shake by the recorded version stellar-cli#2720