feat: add cli to output for graphviz

[stringhandler]

Add a CLI command for outputting a binary program to .dot language, AKA graphviz.

The main reason is to easily compare programs created from SimplicityHL.

For example:
cargo run -- graph 4Am0vN8zP3zuXdYq0DFK50OFg4FN/m2W5xRsrPlArYt8C8wCEChBieAgWBxRsYCAawA=

will output

digraph G {
ordering="out";
  node0[label="unit"];
  node1[label="word(0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)"];
  node2[label="comp"];
  node2->node0;
  node2->node1;
  node3[label="iden"];
  node4[label="pair"];
  node4->node2;
  node4->node3;
  node5[label="iden"];
  node6[label="take"];
  node6->node5;
  node7[label="unit"];
  node8[label="jet(sig_all_hash)"];
  node9[label="comp"];
  node9->node7;
  node9->node8;
  node10[label="pair"];
  node10->node6;
  node10->node9;
  node11[label="witness"];
  node12[label="pair"];
  node12->node10;
  node12->node11;
  node13[label="jet(bip_0340_verify)"];
  node14[label="comp"];
  node14->node12;
  node14->node13;
  node15[label="comp"];
  node15->node4;
  node15->node14;
}

[stringhandler]

It seems that Github has built in support for mermaid diagrams, so I might add an option to export to .dot or .mermaid

flowchart TD
    node0["unit"]
    node1["word(0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798)"]
    node2["comp"]
    node3["iden"]
    node4["pair"]
    node5["iden"]
    node6["take"]
    node7["unit"]
    node8["jet(sig_all_hash)"]
    node9["comp"]
    node10["pair"]
    node11["witness"]
    node12["pair"]
    node13["jet(bip_0340_verify)"]
    node14["comp"]
    node15["comp"]

    node2 --> node0
    node2 --> node1

    node4 --> node2
    node4 --> node3

    node6 --> node5

    node9 --> node7
    node9 --> node8

    node10 --> node6
    node10 --> node9

    node12 --> node10
    node12 --> node11

    node14 --> node12
    node14 --> node13

    node15 --> node4
    node15 --> node14

Loading

[stringhandler]

The actual command also might be better suited for hal-simplicity. Happy to move it there if need be.

[delta1]

Nice one @stringhandler , I do think this fits better in hal-simplicity

[delta1]

Although on second thought it does seem fine in the CLI here 🤷

[stringhandler]

Ok, agreed. I'll leave the logic here, since it is the same place as the other DisplayExpr trait, but move the CLI logic to hal

[apoelstra]

CI breakage looks unrelated (seems we need to update the pins in .github/workflows/fuzz.yml because gitrandom broke us in a patch release) (arguably we should move all this over to rust-bitcoin-maintainer-tools, but that's a much bigger project).

Concept ACK adding this to simpcli for now, but yes, this CLI tool is basically abandoned and we are moving its functionality to hal-simplicity.

[apoelstra]

Super cool that we can just inline the logic and don't need a dependency or anything!

I am a liiitle concerned about the exponential blowup inherent to this, but I think it's okay for now. The CLI tool may want to stick a guard on it and refuse to output more than 2^24 nodes or something without an extra --force flag.