Remove standalone programs lua.c and luac.c (move to lua370-app)

[mgrossmann]

Summary

lua370 is a library. The two standalone programs `lua.c` (LUA interpreter) and `luac.c` (LUA compiler) do not belong in the library project — they are being moved to the new `lua370-app` project which produces the LUA and LUAC load modules.

Problem

• lua370 exports LUA and LUAC as NCALIB members alongside library code
• This causes IEW0241 doubly-defined warnings when embedders (e.g. httpd) link against lua370
• Tracked as roadmap item #24

Changes

• Remove `src/lua.c`
• Remove `src/luac.c`
• No other changes — project type stays `library`, build config unchanged

Follow-up

• Release lua370 v1.0.1 after merge (first version without standalone modules)
• New project `lua370-app` will depend on `lua370 >=1.0.1`