Add adaptive preprocessing escalation and single-receipt test scripts

Preprocessing now tries progressively heavier variants per receipt
(plain -> high-pass -> edge-enhance -> both), stopping as soon as a
cheap LLM-free arithmetic check on the OCR text looks plausible, so
the extra processing only applies to receipts that need it. A flat
version of the same heavier processing regressed the full batch by
helping hard receipts but hurting easy ones; the adaptive version
improves date-matching 37/52 -> 40/52 with no regression (see
testing/2026_10_04_gimp_highpass_nlfilter_experiment.md).

Also adds test_ocr.sh and test_single.sh for checking a single
receipt's OCR text or full pipeline result without a batch run.

tooling-container/src/server.py

@@ -24,9 +24,8 @@ import requests
 from fastapi import FastAPI, HTTPException, UploadFile
 from fastapi.responses import JSONResponse
 
+from adaptive import preprocess_and_ocr_adaptive
 from extract import structure
-from ocr import ocr as run_ocr
-from preprocess import preprocess
 
 OLLAMA_BASE_URL = os.environ.get("OLLAMA_BASE_URL", "http://127.0.0.1:11434")
 OLLAMA_MODEL = os.environ.get("OLLAMA_MODEL", "qwen2.5:3b")
@@ -85,15 +84,10 @@ def health() -> dict:
 def _process_job(job_id: str, image_path: str, scratch_dir: str) -> None:
     try:
         _set_job(job_id, status="preprocessing")
-        final_path = preprocess(image_path, scratch_dir)
-
-        _set_job(job_id, status="ocr")
-        ocr_txt_path = run_ocr(final_path, scratch_dir)
-        with open(ocr_txt_path, "r", encoding="utf-8") as f:
-            ocr_text = f.read()
+        adaptive_result = preprocess_and_ocr_adaptive(image_path, scratch_dir)
 
         _set_job(job_id, status="extracting")
-        result = structure(ocr_text)
+        result = structure(adaptive_result["ocr_text"])
 
         _set_job(job_id, status="done", result=result)
     except Exception as exc:  # noqa: BLE001 - reported to the client, not swallowed