Phase 8: the pack's own JEI pages for every drop source

Adrian, 2026-11-02/03: every item that can drop gets a JEI page naming its
sources, alongside the Cobblemon Info add-on (which shows drops and biomes,
not zones). The companion mod's JEI plugin (jei/DropSourcesJei.kt) adds:
- Pokemon drops on the island: 794 species of lines that live on the
  island, with chances, amounts and the zones they spawn in (or where their
  line lives); spawns with their own drops (Beheeyem in the End). The Drop
  Synthesizer core is the catalyst.
- Guardians and the End boss; Sacrifice Altar tiers and specials; Rebirth
  Chamber; zone ore veins with regrow times; Cobblebase pasture finds per
  skill and zone.

JEI runs on the client, so the pages read assets/cobblesurvival/jei/
drop_sources.json inside the mod, written by tools/jei_sources.py from the
pack's files. Self-tests drop_sources_match_the_server (file vs live server:
drops, zones, own-drop spawns, guardians, End boss, altar) and
jei_pages_build (every page builds, every item exists). The ore a vein gives
moved into world/zones.json (ores -> item), shared with the quest book.
JEI's API (19.64.0.455) is a compile-only dependency from JEI's own Maven.
Self-tests and the island check pass.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/checklists/phase-8.md

@@ -8,12 +8,15 @@
 
 - **Add-ons in the pack:** Cobblemon Quests Reloaded 2.0.2 (Cobblemon task type for FTB Quests) and Cobblemon Info for REI / JEI / EMI 2.32.14. Automated: `quests_have_cobblemon_tasks`, `jei_addon_shows_island_spawns`.
 - **Spawn info in JEI:** right for the pack (species, levels, rarity come from the zone pools), but it shows biomes, not zones; our own pages will add the zone.
+- **JEI pages** (ours): look an item up in JEI (its recipes, key G) for "Pokémon drops on the island" (each Pokémon with its zone and levels), "Guardians and the End boss", "Sacrifice Altar", "Rebirth Chamber", "Zone ore veins" and "Pasture finds". Automated: `drop_sources_match_the_server`, `jei_pages_build`.
 - **Quest book:** 18 chapters, 74 quests, generated from `docs/quests.yaml`: Getting Started, one chapter per zone and the End, Pokémon Machines, Base and Jobs. No rewards, nothing locked. Zone chapters: reach the zone, catch three of its Pokémon, mine its ores, beat its guardian. Automated: `quest_book_loads`, `quest_events_mark_zones` (and the guardian and furnace tests check their quest events).
 
 ## In game (Prism instance)
 
 - [ ] Open JEI, look up a Pokémon (e.g. Pikachu) in Cobblemon Info's pages: the spawn levels match its zone (`docs/zone-species.md`), and its drops are listed.
 
+- [ ] In JEI, look up the recipes of Light Ball: Pikachu's page shows its picture, "Lives in Westmarch (Lv 16–25)" and its drops with chances; Raichu's page says where its line lives. Look up Ender Pearl: Beheeyem in the End has a page of its own.
+- [ ] Look up the recipes of Rare Candy (Sacrifice Altar tiers), Great Ball (Southwold's guardian), Raw Copper (Southwold's veins, and pasture mining in Southwold).
 - [ ] Open the quest book (FTB Quests' book item, or its key): every chapter shows, nodes are joined by lines, none shows a lock.
 - [ ] Getting Started: tick "Welcome to the Island"; catch a Pokémon: "A Partner" completes.
 - [ ] Soft-lock check: get 16 Poké Balls before ticking "Welcome to the Island", then tick it: "Poké Balls" completes too (if it stays stuck, tell me: there's a known flexible-mode bug in older FTB Quests).