feat(cat-gateway): Add document endpoints

[stevenj]

Description

Adds the Signed Document endpoints

Related Issue(s)

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• I have made corresponding changes to the documentation
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[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 370/370}$ | ${\color{red}Fail: 0/370}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 370/370}$ | ${\color{red}Fail: 0/370}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 370/370}$ | ${\color{red}Fail: 0/370}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 370/370}$ | ${\color{red}Fail: 0/370}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 370/370}$ | ${\color{red}Fail: 0/370}$ |

[neil-iohk]

@stevenj Following our conversation earlier I took a look here again, you mentioned using jsonrpc for our API, if so are we going to follow a specific version like 2.0 https://www.jsonrpc.org/specification.

While the spec doesn't explicitly say that method is required it is inferred based on the rest of the context around request format like params where it states it MAY be omitted, if we are following this spec, what approach do you want to take to specify the method, a single document method, or more granular depending on usecase? Should these be defined along with the actions, while they may not be entity specific and more general a list of these may help cover a lot of the usecase examples listed in the API doc.

Depending on the approach here I will hold off updating anything to reflect discussions this morning and I can move relevant API sections into the docs later

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 371/371}$ | ${\color{red}Fail: 0/371}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 371/371}$ | ${\color{red}Fail: 0/371}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 373/373}$ | ${\color{red}Fail: 0/373}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 373/373}$ | ${\color{red}Fail: 0/373}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 385/385}$ | ${\color{red}Fail: 0/385}$ |

[github-actions]

✅ Test Report | ${\color{lightgreen}Pass: 381/381}$ | ${\color{red}Fail: 0/381}$ |