docs(mods): sync docs to the 164-jar kitchen-sink pack

The pack grew 76 -> 164 jars (133 both / 31 client) without any doc
update. Create + ~18 addons filled the tech gap, ars_nouveau + ars_creo
the magic gap, and the full YUNG's/Moog's/TerraBlender set the worldgen
gap, which also resolved the ponderjs orphan.

- 17-mod-shortlist: rewritten around the current pack; gap doc marked
  done, remaining gaps narrowed to map mod, Necronomicon orphan, C2ME.
- 04-mods: jar counts updated; the 24/52 cutover split is now labelled
  historical alongside the current 31/133.
- CLAUDE.md: WS6 partly done, stale "65 default both" line dropped, and
  the ~50-100 mod ceiling flagged as knowingly exceeded in both places.
  MAX_MEMORY 10G was sized for that old assumption - noted for re-check.
- 18-landing-rework: mods.json count 76 -> 164, "50+" stat tile noted
  stale.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plan/04-mods.md

@@ -6,7 +6,8 @@
 
 ## Why drop packwiz
 
-- The packwiz index tracked only **9** mods while the real modset (76 jars) lives
+- The packwiz index tracked only **9** mods while the real modset (76 jars at the
+  time of cutover; 164 as of 2026-07-20) lives
   in the distribution repo — packwiz was half-built and stale.
 - Manual packwiz curation (`.tmpl` render → `refresh` → re-hash) is the flagged
   pain point, and a single missing file (`custom/.gitkeep`) crashlooped the
@@ -20,7 +21,7 @@
 ```
 ulicraft-distribution/dist            (another repo, = $DISTRIBUTION_WEB_ROOT)
   servers/ulicraft-1.21.1/
-    forgemods/required/*.jar          ← 76 jars, Nebula-managed (SOURCE OF TRUTH)
+    forgemods/required/*.jar          ← 164 jars (2026-07-20), Nebula-managed (SOURCE OF TRUTH)
   distribution.json                   ← generated by Nebula; CLIENT install list
         │                                     │
         │ caddy distribution. vhost           │ HeliosLauncher reads it →
@@ -196,8 +197,9 @@ welcomescreen, yeetusexperimentus` — on top of the 11 tomllib auto-caught
 (sodium, sodium-extra, iris, ImmediatelyFast, appleskin, Controlling, BridgingMod,
 CustomSkinLoader, entity_model_features, entity_texture_features, tagtooltips).
 
-**Current state: 24 `client` / 52 `both`.** The 52 may still hide a client-only
-mod that loaded without crashing; if a future restart trips another
+**State at first cutover: 24 `client` / 52 `both`. Current (2026-07-20, post
+tech/magic/worldgen expansion): 31 `client` / 133 `both`.** The `both` set may
+still hide a client-only mod that loaded without crashing; if a future restart trips another
 `invalid dist DEDICATED_SERVER`, flip that one jar to `client` and re-sync — same
 one-line loop. When excluding, prefer leaf mods; if a `both` mod hard-depends on
 the one you exclude you'll get a `Missing mandatory dependency` instead — put it