feat: initial AC telemetry Lua plugin

- CSP Lua app that reads telemetry via ac.* API
- Sends JSON over UDP to configurable target (default 127.0.0.1:5005)
- Purpose-built serializer with zero GC pressure at 60Hz
- Pre-allocated buffer tables, no per-frame allocations
- Graceful fallback when ac global is absent (testing outside AC)
- .gitignore for .idea/

manifest.ini

@@ -0,0 +1,11 @@
+; ACTelemetry - Assetto Corsa CSP Lua Telemetry Plugin
+; Reads car telemetry via the CSP Lua API and sends it as JSON over UDP.
+
+[ABOUT]
+Name = ACTelemetry
+Author = jan
+Version = 1.0.0
+Description = Sends car telemetry data as JSON over UDP for external dashboards and analysis tools.
+
+[SCRIPT]
+Script = main.lua