Fix crash wehn opening some old builds

[unrealdreamz]

Summary

Fixes #522.

• ignore saved jewel socket entries whose itemId no longer exists in the build item list
• make the intuitive-leap radius helper use the existing safe jewel lookup path before reading jewel fields
• add a regression spec for stale socket IDs so malformed saved builds do not poison passive tree state

Root Cause

The issue attachment contains a <Socket nodeId="36044" itemId="13"/> entry, but the saved <Items> list has no <Item id="13">. PassiveSpec:Load still copied that stale ID into self.jewels, leaving later passive tree/radius/loadout code with a socket reference to a missing item.

One crash path was PassiveSpecClass:NodesInIntuitiveLeapLikeRadius, which read item.jewelRadiusIndex before proving that self.build.itemsTab.items[itemId] actually existed.

Fix

PassiveSpec:Load now keeps only socket IDs that resolve to an existing saved item. The radius helper also routes through GetJewel, preserving the invariant that jewel radius logic only sees real jewel items.

This does not invent replacement items or change valid sockets; it only drops stale references that cannot be loaded correctly.

Validation

• gh pr list --repo PathOfBuildingCommunity/PathOfBuilding-PoE2 --state all --search "#522" ... found no active crash/socket fix PR; the only hit was unrelated merged PR Add support for Jarngreipr's Strength mod #1871.
• Issue fixture check against Ice.Slammer.txt: items=18 sockets=5 stale=[(36044, 13)].
• python + lupa syntax compile:
  • PASS lua compile src/Classes/PassiveSpec.lua
  • PASS lua compile spec/System/TestPassiveSpec_spec.lua
• git diff --cached --check: passed.
• git show --check --stat --oneline --no-renames HEAD: passed.

Local Busted/Docker execution was not available in this checkout: lua, luajit, busted, docker, docker-compose were not found on PATH.

Risk / Rollback

Low risk. The load path already treats zero socket item IDs as invalid/empty; this extends that same containment to non-existent positive item IDs. Rolling back restores the previous behavior of retaining stale socket references and risking nil indexing during tree/loadout processing.