node:process — process.env.X = v does not persist (assignment lowering)

[proggeramlug]

Writing process.env. = value then reading it back returns undefined. js_process_env() (process.rs:197) caches the object correctly, so the assignment isn't lowered to a field-set on it. Repro: node-suite/process/env/write. Part of #793.

[proggeramlug]

Fixed by #1371 — process.env writes now persist (node-suite/process/env/write PASSES).

[proggeramlug]

Reopening: the #1371 PR (which closed this) was merged INTO the #1331 PR branch, not into main. When the #1331 reconstruction rebased onto current main, the fix was dropped. Tracking this until either a separate fix PR lands or #1371's content is reopened.