This might be solved by putting the margin on .content and using negative space for full-bleed elements, as in:

  .content { width: 65ch; margin: 0 auto }
  .content .full-bleed {
    width: 100vw;
    margin-left: calc((65ch - 100vw) / 2);
  }

yeah, that's the most common way of doing it afaik

Sounds like Nix or Guix.

Lots of package management systems support these features. Even MSIs from Microsoft despite Windows ironically lacking a centralized repo until recently.

No streamlined enterprise support (insurance), no nix or guix, except for running ON established enterprise linux distributions.

Both nix and guix are happy to run on top of an existing Linux distro.

That's an organizational limitation, not a technical one.