--stealth was a per-subcommand flag defined separately on fetch, serve,
and mcp, and missing from scrape entirely. You could not enable stealth
for parallel scraping, and `obscura --stealth fetch` (flag before the
subcommand) errored.
Promote --stealth to a single global flag like --proxy, so it is valid
before or after any subcommand and applies uniformly to fetch, serve,
scrape, and mcp. scrape now forwards it to its workers via OBSCURA_STEALTH
(mirroring OBSCURA_PROXY), and the bare `obscura` default CDP server
honors it too.
Verified: navigating directly to a blocklisted tracker renders 55503
chars without stealth and 39 (blocked) with it, identically on fetch and
scrape. Obstacle course 33/33.
SGavrl