51 legacy URLs stop 404ing

51 legacy URLs stop 404ing. Every path in Marlon's list that this site had
no rule for. LEGACY_REDIRECTS goes 429 to 480 entries, covering old
/apps/directory/* pages, renamed blog posts, the retired /features and
/experts trees, moved docs pages, and one-off campaign paths.

Diffed against the existing table first: 51 missing, nothing conflicting, so
the change is purely additive.

Every source was checked before it was added. Each of the 51 was requested
against production and answered 404, which is the whole point — they are links
somebody has indexed or bookmarked that currently land on nothing. The check
runs the other way too: a source answering 200 is a live page, and redirecting
it would delete that page. That is why four rows from the first batch were left
out. None of these are in that position. Targets were checked as well; all
resolve.

/updates/page/* is written /updates/page/:path*, which is what Next actually
matches. A bare asterisk is a literal, so the row as supplied would have caught
nothing.

Four /experts/* rows land on /experts, which itself redirects to /, so
those are two hops. Left as the list specifies rather than repointed, so the
intent survives if /experts ever becomes a page again.

Verified on staging: all 52 probes, the 51 rows plus a nested wildcard case,
return 308 to exactly the expected target.