feat: Detect change in externals across shader invocations and suggest alternative

A first instinct when using TypeGPU functions could be to use variables from the outer scope and expect them to auto-update:

let time = 0;

const getDirection = tgpu.fn([], d.vec2f)(() => {
  // Using the `time` variable inside shader code
  return d.vec2f(std.cos(time), std.sin(time));
});

// before render
time += deltaTime;
// draw...

However, the shader will compile with the value that the variable had at the moment of compilation, and not change between invocations.
This is a silent error/bug, and could be hard to grasp on first use.

Possible solution

In DEV mode, we can gather the externals that were used by a shader, and check if their values match the ones that were captured during compilation.

No files, tests, or entry points are named. Start by locating the shader compilation path and how external values are captured, then determine how DEV-mode comparisons and an alternative suggestion should be exposed. Done means changed externals are detected across shader invocations without affecting production behavior.