[Framework] Store Move packages meta on-chain

[pause125]

There may have some meta infomations of Move packages to be stored on-chain.

For example, the upgrading policy. There are two basic policies: compatible, immutable. We need to store the configurations on-chain and check every time publish modules.

[jolestar]

Should we also store the source on-chain?

[pause125]

Should we also store the source on-chain?

I think this should be optional? Maybe some projects don't want to open source.

[pause125]

The designed fields of package meta:

/// Metadata for a package.
struct PackageMetadata has store, drop {
    /// The upgrade policy.
    upgrade_policy: UpgradePolicy,
    /// The upgrade version.
    version: u64,
    /// The module bytes in this package.
    modules: vector<vector<u8>>,
}

Any other ideas? Do we need consider adding new fields of this struct? @jolestar

[jolestar]

Add struct field will break the compatibility.

Add PackageMetadata to the Package's dynamic field?

Keep all modules in PackageMetada is not a good idea. We can continue to keep the modules as package dynamic fields.

[pause125]

1. So we'd better think about what other fields we can put in PackageMetadata
2. I think it's suitable to add PackageMetadata to the Package's dynamic field.
3. modules here means the module source code.

[pause125]

Maybe there's no need to define a new PackageMetadata struct. We can add each meta as Package's dynamic field. In this way, it will be easy to add more meta field in the future if needed.

[jolestar]

The source code can use the module_name.move as the key of the dynamic field.