feat: add LoadReader method to generated funcs

[darkliquid]

Issue #, if available:
#52 #53

Description of changes:

I ended up writing this for my own use before I noticed that there was an existing PR/Issue for this already. Since the other one still hasn't been merged, I figured I may as well throw my hat in the ring as well. By sheer coincidence it's almost identical to the other PR, except for the following:

• I call the function LoadReader instead of LoadFromBinary
• I replace os.ReadFile in Load with os.Open and pass the *os.File to LoadReader, can defer the *os.File.Close()
• I added a simple test
• I used the latest protoc available via mise use protoc as of submitting this PR

When generating the plugin loading functions from protobufs, previously there was only an option to load plugins directly from disk via file names. This prevents use cases such as loading plugins embedded using embed or via an fs.FS virtual filesystem.

To address this, there is now a LoadReader method generated that accepts an io.Reader and uses that via io.ReadAll, rather than having to load a file via os.ReadFile first. The existing Load method has been rewritten to simply call LoadReader with the result of calling the os.Open with the file name.

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[Copilot]

Copilot reviewed 72 out of 72 changed files in this pull request and generated no comments.

[LukaGiorgadze]

@knqyf263 thoughts on this PR?

[knqyf263]

I haven't tested it myself, but if someone else has tested it and confirmed that it works, the change seems fine.

[LukaGiorgadze]

I haven't tested it myself, but if someone else has tested it and confirmed that it works, the change seems fine.

Ok, let's keep it in PR, I'll do testing today.

[SUNsung]

@knqyf263 Will this be added to the master?

[inliquid]

@darkliquid maybe keep LoadBinary as a third option? And probably rename Load, so that all three would be in one place:

• LoadPath
• LoadBinary
• LoadReader

First two will call LoadReader under the hood.

[LukaGiorgadze]

@darkliquid are you planning to make changes?

[darkliquid]

I was not. I'd rather not bloat the PR with additional refactoring work. If we want to add wrappers around LoadReader and/or rename Load I feel that is probably better served as a separate PR that build on top of this one.