docs: document the privacy-filter.cpp backend (#10386)

docs: document the privacy-filter.cpp backend in README and compatibility table

The privacy-filter.cpp backend (#10360) was registered in backend/index.yaml
and referenced from the PII feature docs, but was missing from the backend
catalog surfaces. Add it to the README "Backends built by us" table, the
compatibility table (Utilities & Other, CPU/CUDA 13/Vulkan), and the backend
type list in the backends feature doc.

Assisted-by: Claude:claude-opus-4-8 [Claude Code]

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Co-authored-by: Ettore Di Giacinto <mudler@localai.io>

README.md

@@ -236,6 +236,7 @@ Most backends wrap a best-in-class upstream engine. A handful of them are native
 | [rf-detr.cpp](https://github.com/mudler/rf-detr.cpp) | Native RF-DETR object detection and instance segmentation |
 | [locate-anything.cpp](https://github.com/mudler/locate-anything.cpp) | Open-vocabulary object detection and visual grounding (LocateAnything-3B) |
 | [depth-anything.cpp](https://github.com/mudler/depth-anything.cpp) | Depth Anything 3 monocular metric depth + camera pose estimation |
+| [privacy-filter.cpp](https://github.com/localai-org/privacy-filter.cpp) | Standalone GGML PII/NER token-classification engine powering LocalAI's PII redaction tier |
 | [LocalVQE](https://github.com/localai-org/LocalVQE) | Joint acoustic echo cancellation, noise suppression, and dereverberation |
 | [local-store](https://github.com/mudler/LocalAI) | Local-first vector database for embeddings (shipped in-tree) |
 

docs/content/features/backends.md

@@ -131,6 +131,6 @@ LocalAI supports various types of backends:
 - **Image & Video Generation Backends**: For diffusion models (e.g., stable-diffusion.cpp, diffusers)
 - **Vision & Detection Backends**: For object detection, segmentation, depth, and face/voice recognition (e.g., rf-detr.cpp, locate-anything.cpp, sam3.cpp, insightface)
 - **Audio Processing Backends**: For voice activity detection and audio enhancement (e.g., Silero VAD, LocalVQE)
-- **Utility Backends**: For reranking, fine-tuning, quantization, and vector storage (e.g., rerankers, TRL, local-store)
+- **Utility Backends**: For reranking, PII/NER token classification, fine-tuning, quantization, and vector storage (e.g., rerankers, privacy-filter.cpp, TRL, local-store)
 
 See the [Backend & Model Compatibility Table]({{%relref "reference/compatibility-table" %}}) for the full catalog.

docs/content/reference/compatibility-table.md

@@ -113,6 +113,7 @@ All backends listed here can be installed on demand from the [Backend Gallery]({
 | Backend | Description | Acceleration |
 |---------|-------------|-------------|
 | [rerankers](https://github.com/AnswerDotAI/rerankers) | Document reranking for RAG | CUDA 12, ROCm, Intel SYCL, Metal |
+| [privacy-filter.cpp](https://github.com/localai-org/privacy-filter.cpp) | Standalone GGML engine for the openai-privacy-filter PII/NER token-classification model family (powers LocalAI's PII redaction tier) | CPU, CUDA 13, Vulkan |
 | [local-store](https://github.com/mudler/LocalAI) | Local-first vector database for embeddings | CPU, Metal |
 | [TRL](https://github.com/huggingface/trl) | Fine-tuning (SFT, DPO, GRPO, RLOO, KTO, ORPO) | CPU, CUDA 12/13 |
 | [llama.cpp quantization](https://github.com/ggml-org/llama.cpp) | HuggingFace → GGUF model conversion and quantization | CPU, Metal |