Record swallowed exceptions on their spans

Where an error is caught and logged under a span that would otherwise
stay clean, also record_exception and set ERROR on that span: the
CONSUMER span when a stream message fails, fraud.score_transaction when
the sanctions call times out or fails, and the SERVER span of every
/readyz check (a 503 already made it ERROR, but without the exception).

Left alone where instrumentation already records it: ledger's app-wide
exception handler (FastAPI SERVER span), caught httpx errors (CLIENT
span), and the stream publish failure (PRODUCER span). The consumers'
failed reads run outside any span, so they stay log-only.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

services/fraud/app.py

@@ -3,6 +3,7 @@ from fastapi import FastAPI, Request
 from fastapi.responses import JSONResponse
 from pydantic import BaseModel
 from opentelemetry import trace
+from opentelemetry.trace import StatusCode
 from opentelemetry.instrumentation.fastapi import FastAPIInstrumentor
 
 from common.http import downstream_client
@@ -52,6 +53,9 @@ async def readyz():
     try:
         await redis_client.ping()
     except Exception as exc:
+        span = trace.get_current_span()
+        span.record_exception(exc)
+        span.set_status(StatusCode.ERROR, str(exc))
         logger.exception(f"readyz check failed: {exc}")
         return JSONResponse(status_code=503, content={"status": "unavailable"})
     return {"status": "ok"}
@@ -81,10 +85,14 @@ async def score_transaction(body: ScoreRequest):
                     f"{settings.sanctions_url}/internal/lookup",
                     json={"holder_name": body.holder_name, "request_id": body.request_id},
                 )
-            except httpx.TimeoutException:
+            except httpx.TimeoutException as exc:
+                span.record_exception(exc)
+                span.set_status(StatusCode.ERROR, "sanctions lookup timed out")
                 logger.exception(f"sanctions lookup timed out for request_id={body.request_id}")
                 return JSONResponse(status_code=504, content={"error": "sanctions lookup timed out"})
             except httpx.RequestError as exc:
+                span.record_exception(exc)
+                span.set_status(StatusCode.ERROR, "sanctions lookup failed")
                 logger.exception(f"sanctions lookup failed for request_id={body.request_id}: {exc}")
                 return JSONResponse(status_code=502, content={"error": "sanctions lookup failed"})