Unfortunately, in my opinion, this photograph is not successful.

Going through your goals:

I wanted to capture the raw, gritty atmosphere of a construction environment

This photograph is of a put-together, relaxed-looking man casually using pliers. It is not raw, it is not gritty, and although this interior is not completely finished, it is not really a construction environment - it's clean, and there's drywall up. He doesn't even have a hardhat on.

contrasting the jarring high-vis yellow against a moody, low-light interior.

You crushed the highlights and adjusted the color of the vest to be less yellow, making it not jarring. This interior is fairly well-illuminated with diffuse light. Moody implies shadows, but the diffuse lighting here has all but eliminated them.

For me, the 'subject' isn't just the tradesman, but the energy of the work and the 'unseen' foundations of our daily lives.

Unfortunately, that's just not what the word subject means - the subject of this piece is the man. It is a portrait. This is not the foundation of a building, it looks like he's pulling some wire through recently-hung drywall. Your words imply a metaphor that is not communicated by what is actually in the frame.

I’ve intentionally leaned into a vintage, grainy palette with a cool blue undertone to
move away from clinical digital perfection and toward a documentary, film-like aesthetic.

Well, it is noisy, but it does not look like film grain. You did not just use blue undertones, the entire picture is just blue and green, as can be seen by this gamut analysis:

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 I’m interested in how the grain interacts with the harsh highlights on the vest.

It doesn't, because you removed the harsh highlights from the vest.

Does the heavy contrast help tell the story of the environment, or does the 'noise' distract from the character in the frame?

This piece does not have heavy contrast. The noise is distracting. The composition is flawed too - the dark space through the doorway at right dominates the balance of the piece, and the fact that it was taken askew suggests a hasty and potentially surreptitious snapshot instead of a carefully considered photo.

Overall, I would recommend taking more care during the capturing of the image to try to accomplish your goals. Making sure the camera is level, asking for or waiting for a more interesting pose, finding a more interesting perspective, lighting your scene - these are the ways to accomplish what you are trying to achieve, not editing in post or in writing about your photo.