fix: share-link hydration dead on dev hard loads (useSearchParams dehydration)

[Daren9m]

Root cause

Under next dev (Next 16 / React 19), a hard navigation to any URL with query params left the Suspense boundary around a useSearchParams() consumer permanently dehydrated: the prerendered HTML stayed visible but React never attached — no fibers on the DOM, no effects ever ran — so share-link hydration silently did nothing on /encounters, /maps, /noncombat, and /noncombat/player. Client-side transitions and the production static build were unaffected, which is why it went unnoticed.

Diagnosed by instrumentation, not guesswork: a module-level marker proved the right bundle executes; a fiber check proved the subtree never hydrates on hard loads; the same effect logs twice (StrictMode) and hydrates fine via client-side nav — the one-shot didInit guard (the original suspect) was actually correct.

Fix

In a fully static export, query params are a client-only concern:

• The one-shot hydration effects read new URLSearchParams(window.location.search) directly — effects only run client-side and this never suspends.
• /noncombat/player (which read params during render) now derives its projection from mount-time query state with a popstate listener; the prerendered "Preparing the handout…" state matches the first client render, so hydration is mismatch-free.
• The now-purposeless Suspense wrappers are removed.
• Regression test: a source scan over every page.tsx forbids reintroducing the useSearchParams import/call (red before the fix: 4 failures; green after).

Verification

• Dev hard loads now hydrate on all four pages (verified in-browser: fiber attached, encounter/puzzle/map rendered from seed).
• Replay contract intact: seed 1955118459 reproduces the identical "Skirmish — Ettercap in the Forest" in dev and the production static build; noncombat golden-pin seed 1337 renders "The Constellation Floor" in both the DM view and player handout.
• npm run typecheck clean · npx vitest run 46 files, 691/691 · npm run lint 0 errors · npm run build static export succeeds.

Also includes a one-line autoPort addition to .claude/launch.json (dev convenience; port 3000 was occupied locally).