feat(perps): add headless recipe v1 controller example

[abretonc7s]

Closing this draft because the shape is too intrusive for core.

The correct direction is to keep MetaMask core as a minimal consumer of a reusable Farmslot headless recipe harness instead of embedding a full runner under packages/perps-controller/recipe-v1.

Target replacement shape:

• publish/consume @farmslot/protocol + @farmslot/recipe-harness as dev dependencies;
• keep only a small action manifest + recipe JSON in core;
• use the standard farmslot-recipe CLI for generic headless command/assert/artifact handling;
• if PerpsController-specific coverage is needed, add a tiny package-owned smoke script that calls controller public methods and prints JSON, not a bespoke runner;
• avoid protocol-versioned folder names and broad eslint/tsconfig churn.

This draft is preserved only as a reference for what not to ship.

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Reviewed by Cursor Bugbot for commit 99f5db1. Configure here.}

[cursor]

Truncate checks bytes but slices by characters

Low Severity

The truncate function gates on Buffer.byteLength (a byte-based measure) but then truncates using String.prototype.slice (a character-based operation). For multi-byte UTF-8 strings, a string can have fewer characters than MAX_OUTPUT_BYTES yet more bytes — in that case slice(0, MAX_OUTPUT_BYTES) returns the entire original string unchanged, and the \n…[truncated] suffix is appended, making the output longer than the input while still exceeding the byte budget.

^{Reviewed by Cursor Bugbot for commit 99f5db1. Configure here.}