Invalid C code generated when returning empty seq as `openArray` result from template
### Description

```nim
template foo: openArray[int] =
  @[]

type X = object
  b: seq[int]

let x = X()

echo $foo[x.b[0]]
```

### Nim Version

% nim -v
Nim Compiler Version 2.0.14 [MacOSX: arm64]
Compiled at 2025-01-06
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: bf4de6a394e040d9810cba8c69fb2829ff04dcc6
active boot switches: -d:release


### Current Output

```text
% nim c -r test
Hint: used config file '/Users/etan/Documents/Repos/nimbus-eth2/vendor/nimbus-build-system/vendor/Nim/config/nim.cfg' [Conf]
Hint: used config file '/Users/etan/Documents/Repos/nimbus-eth2/vendor/nimbus-build-system/vendor/Nim/config/config.nims' [Conf]
Hint: used config file '/Users/etan/Documents/Repos/nimbus-eth2/config.nims' [Conf]
........................................................................................................................
CC: test.nim
/Users/etan/Documents/Repos/nimbus-eth2/test.nim:9:340: error: no member named 'Sup' in 'struct TGenericSeq'
    9 |         nimln_(9);      nimZeroMem((void*)T1_, sizeof(tyArray__nHXaesL0DJZHyVS07ARPRA));        T2_ = NIM_NIL;  T2_ = NIM_NIL;  if (((NI)0) < 0 || ((NI)0) >= (x__test_u6.b ? x__test_u6.b->Sup.len : 0)){ raiseIndexError2(((NI)0),(x__test_u6.b ? x__test_u6.b->Sup.len : 0)-1);      }       if (x__test_u6.b->data[((NI)0)] < 0 || x__test_u6.b->data[((NI)0)] >= (T2_ ? T2_->Sup.len : 0)){ raiseIndexError2(x__test_u6.b->data[((NI)0)],(T2_ ? T2_->Sup.len : 0)-1);      }       T1_[0] = _ZN7dollars7dollar_E3int(T2_->data[x__test_u6.b->data[((NI)0)]]);      echoBinSafe(T1_, 1);    popFrame();}
      |                                                                                                                                                                                                                                                                                                                                                                              ~~~  ^
/Users/etan/Documents/Repos/nimbus-eth2/test.nim:9:412: error: no member named 'Sup' in 'struct TGenericSeq'
    9 |         nimln_(9);      nimZeroMem((void*)T1_, sizeof(tyArray__nHXaesL0DJZHyVS07ARPRA));        T2_ = NIM_NIL;  T2_ = NIM_NIL;  if (((NI)0) < 0 || ((NI)0) >= (x__test_u6.b ? x__test_u6.b->Sup.len : 0)){ raiseIndexError2(((NI)0),(x__test_u6.b ? x__test_u6.b->Sup.len : 0)-1);      }       if (x__test_u6.b->data[((NI)0)] < 0 || x__test_u6.b->data[((NI)0)] >= (T2_ ? T2_->Sup.len : 0)){ raiseIndexError2(x__test_u6.b->data[((NI)0)],(T2_ ? T2_->Sup.len : 0)-1);      }       T1_[0] = _ZN7dollars7dollar_E3int(T2_->data[x__test_u6.b->data[((NI)0)]]);      echoBinSafe(T1_, 1);    popFrame();}
      |                                                                                                                                                                                                                                                                                                                                                                                                                                                      ~~~  ^
/Users/etan/Documents/Repos/nimbus-eth2/test.nim:9:471: error: no member named 'data' in 'struct TGenericSeq'
    9 |         nimln_(9);      nimZeroMem((void*)T1_, sizeof(tyArray__nHXaesL0DJZHyVS07ARPRA));        T2_ = NIM_NIL;  T2_ = NIM_NIL;  if (((NI)0) < 0 || ((NI)0) >= (x__test_u6.b ? x__test_u6.b->Sup.len : 0)){ raiseIndexError2(((NI)0),(x__test_u6.b ? x__test_u6.b->Sup.len : 0)-1);      }       if (x__test_u6.b->data[((NI)0)] < 0 || x__test_u6.b->data[((NI)0)] >= (T2_ ? T2_->Sup.len : 0)){ raiseIndexError2(x__test_u6.b->data[((NI)0)],(T2_ ? T2_->Sup.len : 0)-1);      }       T1_[0] = _ZN7dollars7dollar_E3int(T2_->data[x__test_u6.b->data[((NI)0)]]);      echoBinSafe(T1_, 1);    popFrame();}
      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           ~~~  ^
3 errors generated.
Error: execution of an external compiler program 'clang -c  -w -ferror-limit=3 -pthread -I"/Users/etan/Documents/Repos/nimbus-eth2/vendor/nim-libbacktrace" -I"/Users/etan/Documents/Repos/nimbus-eth2/vendor/nim-libbacktrace/install/usr/include" -fvisibility=hidden -mcpu=apple-m1 -fno-omit-frame-pointer -g -O3   -I/Users/etan/Documents/Repos/nimbus-eth2/vendor/nimbus-build-system/vendor/Nim/lib -I/Users/etan/Documents/Repos/nimbus-eth2 -o /Users/etan/Documents/Repos/nimbus-eth2/nimcache/debug/test/@mtest.nim.c.o /Users/etan/Documents/Repos/nimbus-eth2/nimcache/debug/test/@mtest.nim.c' failed with exit code: 1
```

### Expected Output

```text
Either a Nim compile-time error, or a successful compile followed by an IndexDefect at runtime

Error: unhandled exception: index out of bounds, the container is empty [IndexDefect]
```

### Known Workarounds

- Don't return `@[]` from a `template` that returns `openArray`.
- It works fine with `[]` (array instead of seq), or for `@[1]` (non-empty seq)

### Additional Information

_No response_