Fix mod zip layout: set tsconfig rootDir so control.lua lands at mod root

Without an explicit rootDir, tstl computed output paths relative to
tsconfig.json's own directory (modules/events-mod/) rather than the
actual TypeScript source root (src/main/typescript/), so control.lua
and settings.lua ended up nested under src/main/typescript/ in the
packaged mod zip instead of at its root - where Factorio requires them
to be. The mod would not have loaded at all as packaged.

This went uncaught because packageFactorioMod never previously
produced real output (blocked by the now-fixed kxs-ts-gen-core/JitPack
issue). Verified by actually running packageFactorioMod and inspecting
the resulting zip: control.lua, settings.lua and info.json are now at
the root, and control.lua's require() calls ("main.global-init" etc.)
correctly resolve against that flat layout.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

modules/events-mod/tsconfig.json

@@ -7,6 +7,7 @@
     ],
     "module": "commonjs",
     "moduleResolution": "node",
+    "rootDir": "./src/main/typescript",
     "types": [
       "@typescript-to-lua/language-extensions",
       "lua-types/5.2",