Shakedown / Bundle hybrid

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To illustrate the objective, take the following dependency graph.

            ┌───────┐                  
            │       │                  
            │   A   │                  
            │       │                  
            └───────┘                  
                │                      
    ┌───────────┼───────────┐          
    ▼           ▼           ▼          
┌───────┐   ┌───────┐   ┌───────┐      
│       │   │       │   │       │      
│   B   │   │   C   │   │   D   │      
│       │   │       │   │       │      
└───────┘   └───────┘   └───────┘      
                            │          
                      ┌─────┴─────┐    
                      ▼           ▼    
                  ┌───────┐   ┌───────┐
                  │       │   │       │
                  │   E   │   │   F   │
                  │       │   │       │
                  └───────┘   └───────┘
                                  │    
                                  │    
                                  ▼    
                              ┌───────┐
                              │       │
                              │   G   │
                              │       │
                              └───────┘

The D-subtree is isolated from the rest of the dependency graph. This plugin (or extension of
interlock-shakedown) should perform Rollup.js-like processing for the D-subtree only. E, F, and G
should be merged into D using the same patterns already used in interlock-shakedown and then
pruned from the tree.

This will reduce start-up times for small modules, allow for DCE on the isolated parts of the graph,
and result in smaller bundles.