Network log: response body silently dropped when entry rotates out before fetchRequestBodyUpdate arrives #1390

Problem

FetchRequestLogState.onFetchRequestBodyUpdate patches the response body onto the matching entry by id:

const idx = this.fetchRequests.findIndex((e) => e.id === id);
if (idx === -1) return; // silent no-op

The body read is deferred (fire-and-forget tee'd stream in fetchTracking.ts). On a chatty transport log, if ≥maxFetchRequests (default 1000) newer requests arrive between the fetchRequest append and the deferred fetchRequestBodyUpdate, the original entry is evicted by rotation, so the update finds idx === -1 and silently drops the body. The user sees (empty) in the Response Body section with no way to tell "body never came back" from "body was dropped after eviction."

Not a correctness bug (the entry is gone anyway) and irrelevant for auth traffic (sparse), but invisible.

Suggested fix

Emit a logger.debug at the early-return site so the drop is traceable — blocked on a logger being plumbed into the state managers (they don't have one today). Track that dependency here.

Context

Surfaced in the 7th-pass review of #1387 (#1386), which introduced the auth body-capture path. Out of scope for that PR.