fix(mapping): 对齐全局模型映射的正则匹配行为与范围 (#296)

- scheduler_core: `matches_model_mapping` 改为大小写不敏感且整串匹配，并补充单测
- global model routing 预览:
  - Key 过滤增加 `allowed_models + model_mappings` 校验
  - `all_keys_whitelist` 改为收集全站活跃 Provider 的活跃 Key 白名单
- provider mapping-preview:
  - 优先使用 admin 全量 GlobalModel（含非激活）参与映射
  - admin 数据为空时回退 public 模型，保持兼容
- public models 匹配逻辑统一复用 scheduler_core 实现，避免行为分叉
- 更新网关测试，覆盖未关联 Provider 的 Key 也进入 whitelist 的场景

apps/aether-gateway/src/handlers/public/support/models/shared.rs

@@ -1,7 +1,7 @@
 use aether_data_contracts::repository::candidate_selection::{
     StoredMinimalCandidateSelectionRow, StoredProviderModelMapping,
 };
-use regex::Regex;
+use aether_scheduler_core::matches_model_mapping;
 
 use super::GatewayPublicRequestContext;
 
@@ -103,10 +103,7 @@ fn candidate_model_names_for_models(
 }
 
 pub(crate) fn matches_model_mapping_for_models(pattern: &str, model_name: &str) -> bool {
-    let Ok(compiled) = Regex::new(&format!("^(?:{pattern})$")) else {
-        return false;
-    };
-    compiled.is_match(model_name)
+    matches_model_mapping(pattern, model_name)
 }
 
 fn row_exposes_global_model_for_models(