fix(infra): correct Jaeger image tag (#58)

## Summary
`jaegertracing/all-in-one:1.62` doesn't exist on Docker Hub — I picked it from memory in #57 without verification. Jaeger 1.x publishes only full-semver tags (1.X.Y), not rolling minor (`1.X`) tags.

Activating `--profile observability` errored at image-pull time:

```
Error response from daemon: failed to resolve reference
"docker.io/jaegertracing/all-in-one:1.62": not found
```

Pin to `1.76.0` (latest stable in the 1.x line, verified against Docker Hub).

## Test plan
- [ ] `cd infra/local && docker compose -f dev.compose.yml --profile observability up -d` → all images pull, all services healthy.
- [ ] http://localhost:16686 → Jaeger UI loads (empty until the BFF starts emitting traces, which lands in the upcoming **B — Observability foundations** PR).
- [ ] Renovate's docker-compose manager picks up future Jaeger 1.x bumps and surfaces them as PRs.

---------

Co-authored-by: Julien Gautier <julien.gautier@apf.asso.fr>
Reviewed-on: #58

infra/local/dev.compose.yml

@@ -123,7 +123,7 @@ services:
   # Jaeger on the internal Compose network.
   # ------------------------------------------------------------------
   jaeger:
-    image: jaegertracing/all-in-one:1.62
+    image: jaegertracing/all-in-one:1.76.0
     container_name: apf-portal-jaeger
     restart: unless-stopped
     profiles: [observability]