BUG: Missing ok check on type assertion in HTTP tests

[andrinoff]

Describe the bug

In plugin/http_test.go line 58, type assertion lacks ok check:

headers := tbl.RawGetString("headers").(*lua.LTable)

If headers field isn't *lua.LTable, panic occurs instead of proper error.

To reproduce

1. Modify test to return non-table value for headers
2. Test panics instead of failing gracefully
3. No useful error message

Expected behavior

Use safe type assertion:

headersVal := tbl.RawGetString("headers")
headers, ok := headersVal.(*lua.LTable)
if !ok {
    t.Fatalf("expected headers to be table, got %T", headersVal)
}

Screenshots

N/A

Additional context

• File: plugin/http_test.go
• Line: 58
• Severity: Medium - test crashes vs proper failure
• Fix complexity: Easy - add ok check pattern