[jm-rivera]

Fixes from a review of the website release (dev into main, #81). None of these breaks a page on its own, but three need to ship with that release: crawlers would be counted as share and embed views, a shared gallery search would lose its preview card, and once dfo-ai's planner decisions ship an approved plan would file them under "Counted as".

• Crawlers no longer record events. track (src/lib/events/track.ts) returns before the log line, the database row and the PostHog forward when the request comes from a bot (isBotRequest in the new src/lib/bot.ts, on the isbot package the repo pins). The release opens /s/ and /embed/ to crawlers, and the event table keeps no user agent, so those rows could not be told apart later. requestLog.ts uses the same check.
• Every page's openGraph comes from pageOpenGraph (src/lib/site.ts), which keeps the site name and the root card image unless a page has its own card, so /data?share=<gallery id> previews with the image again.
• /data?spec= and a /data?share= that is not a gallery dataset now send X-Robots-Tag: noindex, nofollow (noindexHeaders in src/lib/crawl.ts), so their noindex no longer depends on when the streamed metadata reaches the head. A test matches each URL with Next's own getPathMatch and matchHas and checks the header agrees with the page metadata.
• An approved plan files planner decisions under their own heading by choice_id (approvedView in src/lib/studio/plan.ts), which dfo-ai sends on plan.approved from ai#106. A plan stored in a chat before that has no ids and reads as before.
• A chip the harness refuses (422 scope_choice_stale) no longer spends a guest prompt (withRefusedChip marks it refunded, Studio.tsx subtracts it).
• The merged entity menu numbers groups that share a wording ("Congo (1)", "Congo (2)") in entity_choice order (entityChoiceLabels).
• A stale switch refused without a current card ends read-only with no Approve bar (refusedSwitch), and canSwitch and isStale are the single tests the plan code uses.

Testing: lint, CSS lint, typecheck and build pass; the full test suite passes (2,078, including the database suite) and the later search, studio and chat runs pass (1,609). Each change has a test that fails on dev. Under next start, /data?share=zzzz and /data?spec=x send the header and a gallery share does not.