feat: provider api_formats 可空继承、OpenAI 图片 edit/variation 与用量配额多项补强

- 鉴权: provider_api_keys.api_formats 改为可空，OAuth 托管 key 自动继承 provider endpoints 激活格式，相关 handler/测试同步更新
- 图片 planner: OpenAI 图片路由新增 edit/variation 操作并完善参数校验、响应合并与流式处理
- 用量: user me usage 返回区分 client_requested_stream/upstream_is_stream，前端 usage 列表筛选与展示增强
- 统计: stats_daily_model 新增 cache_creation_ephemeral_5m/1h tokens 字段与回填链路
- 配额/observability: quota repository 新增内存与 SQL 扩展，admin observability usage 字段扩充
- 其它: OAuth 导入/轮询收敛、provider 汇总与 pool admin 读写链路小修、新增 system_config 缓存与 provider template handler

Closes #318

Co-authored-by: Entropy.Xu <53283266+Entropy-Xu@users.noreply.github.com>

crates/aether-data/src/repository/provider_catalog/sql.rs

@@ -249,19 +249,22 @@ SELECT
   provider_id,
   COALESCE(NULLIF(name, ''), id) AS name,
   COALESCE(NULLIF(auth_type, ''), 'summary') AS auth_type,
-  capabilities,
+  NULL::jsonb AS capabilities,
   is_active,
   api_formats,
   'summary' AS api_key,
-  NULL::text AS auth_config,
+  CASE
+    WHEN auth_config IS NULL THEN NULL
+    ELSE '{}'::text
+  END AS auth_config,
   NULL::text AS note,
-  internal_priority,
-  rate_multipliers,
-  global_priority_by_format,
+  NULL::integer AS internal_priority,
+  NULL::jsonb AS rate_multipliers,
+  NULL::jsonb AS global_priority_by_format,
   NULL::jsonb AS allowed_models,
   NULL::bigint AS expires_at_unix_secs,
-  cache_ttl_minutes,
-  max_probe_interval_minutes,
+  NULL::integer AS cache_ttl_minutes,
+  NULL::integer AS max_probe_interval_minutes,
   NULL::jsonb AS proxy,
   NULL::jsonb AS fingerprint,
   NULL::integer AS rpm_limit,
@@ -274,27 +277,27 @@ SELECT
   NULL::jsonb AS utilization_samples,
   NULL::bigint AS last_probe_increase_at_unix_secs,
   NULL::integer AS last_rpm_peak,
-  request_count,
+  NULL::integer AS request_count,
   0::bigint AS total_tokens,
   0::double precision AS total_cost_usd,
-  success_count,
+  NULL::integer AS success_count,
   NULL::integer AS error_count,
-  total_response_time_ms,
-  EXTRACT(EPOCH FROM last_used_at)::bigint AS last_used_at_unix_secs,
-  auto_fetch_models,
+  NULL::integer AS total_response_time_ms,
+  NULL::bigint AS last_used_at_unix_secs,
+  FALSE AS auto_fetch_models,
   NULL::bigint AS last_models_fetch_at_unix_secs,
   NULL::text AS last_models_fetch_error,
   NULL::jsonb AS locked_models,
   NULL::jsonb AS model_include_patterns,
   NULL::jsonb AS model_exclude_patterns,
   NULL::jsonb AS upstream_metadata,
-  EXTRACT(EPOCH FROM oauth_invalid_at)::bigint AS oauth_invalid_at_unix_secs,
-  oauth_invalid_reason,
+  NULL::bigint AS oauth_invalid_at_unix_secs,
+  NULL::text AS oauth_invalid_reason,
   NULL::jsonb AS status_snapshot,
-  EXTRACT(EPOCH FROM created_at)::bigint AS created_at_unix_ms,
-  EXTRACT(EPOCH FROM updated_at)::bigint AS updated_at_unix_secs,
+  NULL::bigint AS created_at_unix_ms,
+  NULL::bigint AS updated_at_unix_secs,
   health_by_format,
-  circuit_breaker_by_format
+  NULL::jsonb AS circuit_breaker_by_format
 FROM provider_api_keys
 WHERE provider_id IN (
 "#;