## Description 

This adds support for `init` on upgrade according to the following
rules:
1. `init` functions are only called in new modules introduced in that
upgrade;
2. It is an error (now) to add an `init` function to an existing module
during an upgrade;
3. `init` functions in new modules at upgrade are called in the order
they appear in the `Upgrade` command.

Init functions in upgrades introduce restrictions on the global LUMPY
linkage as follows:
1. If the package being upgraded (of any version) doesn't occur in the
PTB then any `Upgrade` commands that have `init` functions introduce
`exact` constraints (just like `Publish`).
2. If package being upgraded (of any version) occurs in the PTB then for
any `(original_id, version_id)` as defined in the `Upgrade` command
either: a. It is not in the existing LUMPY linkage, and a `original_id
-> exact(version_id)` constraint is introduced; or b. It is in the
existing LUMPY linkage, in which case `LUMPY[original_id].id` must equal
`version_id`.

Ignore exact protocol versions -- once we're ready to land this I'll do
that whole song and dance.

## Test plan 

Added a bunch of new tests, updated existing tests (and also made these
protocol-versioned tests to memorialize them).

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## Release notes

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- [ ] Protocol: 
- [ ] Nodes (Validators and Full nodes): 
- [ ] gRPC:
- [ ] JSON-RPC: 
- [ ] GraphQL: 
- [ ] CLI: 
- [ ] Rust SDK:
- [ ] Indexing Framework: