docs: add README with ParadeDB setup and usage instructions

Author: Restodecoca

llama-index-integrations/vector_stores/llama-index-vector-store-paradedb/README.md

@@ -0,0 +1,90 @@
+# LlamaIndex Vector Stores Integration: ParadeDB
+
+This module adds full ParadeDB integration enabling hybrid search with BM25 and vector similarity (HNSW) in PostgreSQL.
+
+---
+
+## Quick Setup
+
+---
+
+### 1. **Setup example**
+
+Run ParadeDB locally:
+
+```bash
+docker run --name paradedb \
+  -e POSTGRES_USER=postgres \
+  -e POSTGRES_PASSWORD=mark90 \ 
+  -e POSTGRES_DB=postgres \
+  -p 5432:5432 \
+  -d paradedb/paradedb:latest
+```
+
+---
+
+### 2. **Usage example**
+
+```python
+import os
+from dotenv import load_dotenv
+from sqlalchemy import make_url
+from llama_index.vector_stores.paradedb import ParadeDBVectorStore
+
+def get_vector_store(table_name: str = "pgvector") -> ParadeDBVectorStore:
+    """
+    Creates and returns a new ParadeDBVectorStore instance using environment variables.
+    """
+    load_dotenv()
+
+    host = os.getenv("DB_HOST")
+    port = os.getenv("DB_PORT")
+    user = os.getenv("DB_USER")
+    password = os.getenv("DB_PASSWORD")
+    database = os.getenv("DB_DATABASE")
+
+    connection_string = f"postgresql://{user}:{password}@{host}:{port}"
+    url = make_url(connection_string)
+
+    return ParadeDBVectorStore.from_params(
+        database=database,
+        host=url.host,
+        password=url.password,
+        port=url.port,
+        user=url.username,
+        table_name=table_name,
+        text_search_config="english",
+        hybrid_search=True,  # needed to use bm25
+        use_bm25=True,
+        embed_dim=int(os.getenv("EMBEDDING_DIM")),
+        hnsw_kwargs={
+            "hnsw_m": 16,
+            "hnsw_ef_construction": 64,
+            "hnsw_ef_search": 40,
+            "hnsw_dist_method": "vector_cosine_ops",
+        },
+    )
+```
+
+---
+
+### Notes
+
+* Set `hybrid_search=True` and `use_bm25=True` to enable **hybrid BM25 + vector** retrieval.
+* You **must** use the `paradedb/paradedb:latest` image — not `pgvector/pgvector`.
+* The default schema name is `paradedb` to enable BM25.
+* Fully compatible with **llama-index-core** and other vector store interfaces.
+
+---
+
+### Disclaimer
+
+This integration was based on the Postgres Vector Store implementation:
+
+**version = "0.5.5"**
+
+
+However, **`customize_query_fn`** and other Postgres-specific query customization features are **not supported** in this ParadeDB version, as the focus here is on BM25 and hybrid retrieval.
+
+Feel free to contribute and extend this module further.
+