Harden queue runtime correctness boundaries

[julia-script]

Summary

• harden storage decoding, Redis scalar and cursor validation, and Lua state transitions
• correct wait, retry, interruption, terminal-result, offer-option, lease, and worker configuration behavior
• add adversarial regression coverage and synchronize the generated Lua artifact
• document the tightened runtime contracts and keep the prerelease line at 0.3.0-rc with a patch changeset

Validation

• pnpm check
• pnpm test — 155 passed, 2 environment-specific skips
• pnpm verify:package — 88 packed entries verified
• git diff --check origin/main...HEAD

The runtime-correctness implementation went through three independent review/fix cycles. The branch was then rebased onto current main; it now contains one unique commit and merges without textual conflicts.