E2E: Remove redundant `[e2e]` prefix from log output

[phyllis-sy-wu]

Problem/Feature

Every E2E log line starts with [e2e], e.g.:

[e2e][w0][browser] uninstalling app from store
[e2e][w0][cli] exec: node .../run.js app deploy
[e2e][w0] ----- SETUP: store e2e-w0-123 -----

The [e2e] prefix is redundant — we're already running E2E tests, so every line is obviously E2E. It adds visual noise without information.

Proposed Solution

Remove the [e2e] prefix from everywhere. Output becomes:

[w0][browser] uninstalling app from store
[w0][cli] exec: node .../run.js app deploy
[w0] ----- SETUP: store e2e-w0-123 -----

Small change in setup/env.ts, no test code changes.