fix: increase classifier timeouts to handle sidecar cold starts

Receive timeout 15s → 25s, task yield 20s → 30s. The classifier
sidecar accepts TCP connections before models finish loading, causing
timeouts on cold starts.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: emilwojtaszek

lib/ksef_hub/invoice_classifier.ex

@@ -67,7 +67,7 @@ defmodule KsefHub.InvoiceClassifier do
 
     [cat_result, tag_result] =
       [cat_task, tag_task]
-      |> Task.yield_many(:timer.seconds(20))
+      |> Task.yield_many(:timer.seconds(30))
       |> Enum.map(fn
         {_task, {:ok, result}} ->
           result

lib/ksef_hub/invoice_classifier/client.ex

@@ -13,7 +13,7 @@ defmodule KsefHub.InvoiceClassifier.Client do
 
   require Logger
 
-  @receive_timeout 15_000
+  @receive_timeout 25_000
 
   @doc "Predicts a category for the given invoice input."
   @spec predict_category(map(), map()) :: {:ok, map()} | {:error, term()}