Fix HIGH priority issues: unbounded queries, rate limiting, health checks

Issue #3 - Unbounded Query Results (OOM):
- get_all_archived_history() now uses keyset pagination with bounded max_rows (50k default)
- Added 'id' field to records from get_archived_history() and get_archived_history_keyset()
- Protocol signature updated with page_size, max_rows, last_ban_id params

Issue #7 - Docker Health Check Fails:
- Added curl to Dockerfile.backend runtime image
- HEALTHCHECK now uses 'curl -f http://localhost:8000/api/health'
- compose.prod.yml: increased start_period to 40s, timeout to 10s
- Frontend healthcheck proxies to backend /api/health

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

backend/app/mappers/history_mappers.py

@@ -0,0 +1,81 @@
+"""History response mappers.
+
+Convert domain models (from history_service) to response models (for HTTP API).
+
+This is the mapping layer at the router boundary, ensuring the service layer
+remains independent of HTTP response shapes.
+"""
+
+from __future__ import annotations
+
+from app.models.history import (
+    HistoryBanItem,
+    HistoryListResponse,
+    IpDetailResponse,
+    IpTimelineEvent,
+)
+from app.models.history_domain import (
+    DomainHistoryBanItem,
+    DomainHistoryList,
+    DomainIpDetail,
+    DomainIpTimelineEvent,
+)
+from app.utils.pagination import create_pagination_metadata
+
+
+def map_domain_history_ban_item_to_response(
+    domain: DomainHistoryBanItem,
+) -> HistoryBanItem:
+    """Convert domain history ban item to response model."""
+    return HistoryBanItem(
+        ip=domain.ip,
+        jail=domain.jail,
+        banned_at=domain.banned_at,
+        ban_count=domain.ban_count,
+        failures=domain.failures,
+        matches=domain.matches or [],
+        country_code=domain.country_code,
+        country_name=domain.country_name,
+        asn=domain.asn,
+        org=domain.org,
+    )
+
+
+def map_domain_history_list_to_response(domain: DomainHistoryList) -> HistoryListResponse:
+    """Convert domain history list to response model."""
+    return HistoryListResponse(
+        items=[map_domain_history_ban_item_to_response(i) for i in domain.items],
+        pagination=create_pagination_metadata(
+            domain.total, domain.page, domain.page_size
+        ),
+    )
+
+
+def map_domain_ip_timeline_event_to_response(
+    domain: DomainIpTimelineEvent,
+) -> IpTimelineEvent:
+    """Convert domain IP timeline event to response model."""
+    return IpTimelineEvent(
+        jail=domain.jail,
+        banned_at=domain.banned_at,
+        ban_count=domain.ban_count,
+        failures=domain.failures,
+        matches=domain.matches or [],
+    )
+
+
+def map_domain_ip_detail_to_response(domain: DomainIpDetail) -> IpDetailResponse:
+    """Convert domain IP detail to response model."""
+    return IpDetailResponse(
+        ip=domain.ip,
+        total_bans=domain.total_bans,
+        total_failures=domain.total_failures,
+        last_ban_at=domain.last_ban_at,
+        country_code=domain.country_code,
+        country_name=domain.country_name,
+        asn=domain.asn,
+        org=domain.org,
+        timeline=[
+            map_domain_ip_timeline_event_to_response(t) for t in (domain.timeline or [])
+        ],
+    )