feat: create a script generator

[tdelabro]

Currently we create scripts in order to test our opcodes implementation.
It is done with a []u8 looking like this:

const bytes: [?]u8 = [_]u8{ 0x12, 0x34, 0x56, 0x78 };

Where everything (opcode and data) is written as u8.
This is unreadable and unmaintainable.

I want it to look like this:

const my_script = ScriptBuilder.new().pushOpcode(Opcode.OP_ADD).pushInt(1).pushInt(1).addOpcode(Opcode.OP_NUMEQUAL).addInt(2).build();

Create in as an independent lib, script/

[onlydustapp]

Hey @89oso!
Thanks for showing interest.
We've created an application for you to contribute to btczee.
Go check it out on OnlyDust!

[varun-doshi]

Hey @tdelabro
I can take this up. Been working with Zig the past few weeks.
I probably have a good idea how to get this done

[onlydustapp]

Hey @varun-doshi!
Thanks for showing interest.
We've created an application for you to contribute to btczee.
Go check it out on OnlyDust!

[tdelabro]

Hey @89oso, as this is an advanced issue and you have not contributed yet to the project, I will assign it to @varun-doshi and ask you to start with an easier, smaller issue.

[varun-doshi]

I see this

btczee/src/script/lib.zig

Line 11 in d11b780

const MAX_OPS_PER_SCRIPT = 201;

Would it be right to assume our ScriptBuilder will only hold max of 201 opcodes at any given time?

[varun-doshi]

Also something to note @tdelabro
Zig seems to have an inherent issue with function chaining:
ziglang/zig#5705

I've come up with 2 ways to use the ScriptBuilder. Will clarify in my PR.
We can choose whichever seems to be simpler syntax wise