chore(data): weekly link freshness pass - #21

Google's documentation redirects to whichever locale it infers from the client.
The checker followed those redirects and recorded the destination as canonical,
so a --fix pass pinned English rows to whatever language the runner looked like
that day: 212 URLs across the dataset carried ?hl=pt-br, ?hl=ar, ?hl=he and
similar. None were there before #17 — this was my regression, and the first
automated PR (#21) was about to add six more.

Two changes. Requests now send Accept-Language: en-US,en;q=0.9, so the redirect
mostly does not happen. And normalise() drops language-selection parameters, so a
redirect that only picks a translation classifies as `ok` rather than `moved` and
never produces a correction. A genuine move that happens to land on a localised
URL still counts as moved, with the language stripped before it is written.

--fix now also strips language parameters an earlier pass baked in: 212 cleaned,
zero remaining.

Side effect worth noting: `moved` drops from 41.7% at the baseline to 0.1%. Some
of that fall was the redirect repair working, but part of the original figure was
this bug counting translations as moves.

Co-authored-by: AvaKim <avajiyo@gmail.com>
Co-authored-by: Claude Opus 5 <noreply@anthropic.com>