chore: :arrow_up: Update leejet/stable-diffusion.cpp to c8fb3d245858d495be1f140efdcfaa0d49de41e5 (#8841)

* chore: :arrow_up: update stable-diffusion.cpp to `c8fb3d245858d495be1f140efdcfaa0d49de41e5`

Update stablediffusion-ggml to include fix for SD1 Pix2Pix issue
(leejet/stable-diffusion.cpp#1329).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Signed-off-by: localai-bot <localai-bot@noreply.github.com>

* fix: address CI failures in stablediffusion update

Signed-off-by: localai-bot <localai-bot@noreply.github.com>

* fix: resolve remaining CI failures in stablediffusion update

- Move flow_shift to global scope so gen_image() can access the value
  set during load_model() (was causing compilation error)
- Fix sd_type_str array: TQ1_0 should be at index 34, TQ2_0 at index 35
  to match upstream SD_TYPE_TQ1_0=34, SD_TYPE_TQ2_0=35 enum values

Signed-off-by: localai-bot <localai-bot@noreply.github.com>
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Signed-off-by: localai-bot <localai-bot@noreply.github.com>
Co-authored-by: localai-bot <localai-bot@noreply.github.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>