Add ParadeDB external search backend

Introduce an optional search backend that indexes public/unlisted Notes into a separate ParadeDB (pg_search) Postgres and queries it for status search results.

config/config.exs

@@ -938,6 +938,14 @@ config :pleroma, Pleroma.Search.Meilisearch,
   private_key: nil,
   initial_indexing_chunk_size: 100_000
 
+config :pleroma, Pleroma.Search.ParadeDB,
+  url: nil,
+  table: "pleroma_search_documents"
+
+config :pleroma, Pleroma.Search.ParadeDB.Repo,
+  pool_size: 10,
+  prepare: :unnamed
+
 config :pleroma, Pleroma.Application,
   background_migrators: true,
   internal_fetch: true,

config/description.exs

@@ -3503,7 +3503,12 @@ config :pleroma, :config_description, [
         key: :module,
         type: :keyword,
         description: "Selected search module.",
-        suggestion: [Pleroma.Search.DatabaseSearch, Pleroma.Search.Meilisearch]
+        suggestion: [
+          Pleroma.Search.DatabaseSearch,
+          Pleroma.Search.Meilisearch,
+          Pleroma.Search.QdrantSearch,
+          Pleroma.Search.ParadeDB
+        ]
       }
     ]
   },
@@ -3536,6 +3541,28 @@ config :pleroma, :config_description, [
       }
     ]
   },
+  %{
+    group: :pleroma,
+    key: Pleroma.Search.ParadeDB,
+    type: :group,
+    description: "ParadeDB settings.",
+    children: [
+      %{
+        key: :url,
+        type: :string,
+        description:
+          "ParadeDB database URL (separate Postgres instance). " <>
+            "Can also be set via `PARADEDB_DATABASE_URL`.",
+        suggestion: ["postgres://postgres:postgres@127.0.0.1:5432/paradedb"]
+      },
+      %{
+        key: :table,
+        type: :string,
+        description: "Table name used for search documents.",
+        suggestion: ["pleroma_search_documents"]
+      }
+    ]
+  },
   %{
     group: :pleroma,
     key: Pleroma.Language.LanguageDetector,