Add GOPACS integration documentation

[Miggets7]

Summary

• Adds a GOPACS.md file alongside the GOPACS source code with high-level documentation
• Covers: what GOPACS is, user setup requirements, developer component overview, UFTP data flow, and testing references
• Links to official GOPACS documentation rather than duplicating content

Resolves #10

[Copilot]

Pull request overview

Adds high-level documentation for the EMS GOPACS integration, colocated with the GOPACS manager implementation, to address issue #10 and provide setup + developer orientation without duplicating upstream GOPACS docs.

Changes:

• Introduces GOPACS.md describing GOPACS/UFTP context and linking to official GOPACS documentation.
• Documents user setup requirements and OpenRemote manager configuration (env vars, asset setup).
• Summarizes internal components, message/data flow, inbound endpoint, auth/signing, and testing references.

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[MartinaeyNL]

Here are some of my findings of the GOPACS.md file you've created.
I don't have a lot of prior GOPACS knowledge, therefore I was able to assess "if people with less knowledge could understand this".

Please take a look at my comments, the ones from Copilot,
and I would recommend taking a second look yourself, to make sure everything is described correctly, and can be understood by people like me 👍

[MartinaeyNL]

I assume it should be "We accept or reject the offer from the DSO" ?
Because, from my understanding, Step 3 sends an offer, and we can either reject/accept it by "responding" in Step 4.
Then in Step 5 we can "order" based on the offer that we agreed upon earlier.

And if I misunderstand this, then the docs are not clear enough 😂

[Miggets7]

We send the offer, as AGR to the DSO. They accept/reject it by sending a FlexOfferResponse

[MartinaeyNL]

We send the offer, as AGR to the DSO.

I have no clue what an AGR is. 😂

They accept/reject it by sending a FlexOfferResponse

Wait, then the direction of the arrows in the diagram don't make sense right?
(if they send a Response, instead of us responding)

[Miggets7]

it says it here:

OpenRemote acts as an AGR (Aggregator) in the UFTP protocol.

It starts with a FlexRequest from the DSO. We respond with a FlexRequestResponse
Then we send a FlexOffer to the DSO. They respond with a FlexOfferResponse
Then they send a FlexOrder and we respond back with a FlexOrderResponse

So I think the lines are correct. Maybe read it once again? #

[MartinaeyNL]

OOOHHH I've indeed read it the wrong way around.
I assumed that the left column was OpenRemote, and the right one the DSO.
Maybe because I tend to think from the perspective of the OpenRemote integration.

I think I understand it now.

[MartinaeyNL]

I was able to understand most of the documentation without much prior knowledge of GOPACS.
Although it might be worth taking a second look yourself @Miggets7 to make sure everything is described
correctly, and can be understood by people like me. 👍

[MartinaeyNL]

Thanks!