Endo: Support cyclic dependencies across compartments

[kriskowal]

Agoric contracts use these mutually-dependent packages:

• https://www.npmjs.com/package/es-abstract
• https://www.npmjs.com/package/string.prototype.trimleft

To facilitate this, Endo will need to implement a two-pass assemble method and not use moduleMapHook instead of moduleMap for all dependencies. In the first, flat pass over the compartment map, it will construct all of the compartments, passing the evolving compartment map to each child compartment. This pass will no longer be recursive and will not detect import cycles. The load phase will allow cross-linkage by referring to the compartment map in the moduleMapHook.

[kriskowal]

Done and released!