fix(hub): 实例级 dir_aliases 目录别名映射，根治远程 Windows 实例误传 POSIX 路径

- config.json / config.example.json: lan-189、lan-204 增加 dir_aliases 映射
  (/sc-data/cfc -> C:/code/cfc 或 D:/cfc)，供调度器将误传的 POSIX 路径重映射
  回实例真实根目录
- 同步实例配置演进（concurrency_limit、model_chain、auto_prod 等，
  与 hub.py instances 实测一致）

背景：Git Bash(MSYS) 传参给 Windows 原生 python.exe 时会把 /sc-data/...
自动加 PortableGit 前缀转成 Windows 路径；配合 dir_aliases 后调度器可还原
并重映射，避免 lan-189 上出现 LocationNotFound 或错误目录。

tools/xaf_agent_hub/config.example.json

@@ -55,7 +55,8 @@
       "password_env": "XAF_HUB_PW_LAN_204",
       "cfc_roots": ["D:\\cfc"],
       "default_directory": "D:\\cfc",
-      "branch_policy": "mainline"
+      "branch_policy": "mainline",
+      "dir_aliases": {"/sc-data/cfc": "D:/cfc"}
     },
     {
       "name": "lan-189",
@@ -63,7 +64,8 @@
       "password": null,
       "password_env": "XAF_HUB_PW_LAN_189",
       "cfc_roots": ["C:\\code\\cfc"],
-      "default_directory": "C:\\code\\cfc"
+      "default_directory": "C:\\code\\cfc",
+      "dir_aliases": {"/sc-data/cfc": "C:/code/cfc"}
     },
     {
       "name": "prod-etotem",

tools/xaf_agent_hub/config.json

@@ -1,6 +1,6 @@
 {
   "version": 2,
-  "concurrency_limit": 2,
+  "concurrency_limit": 4,
   "session_ttl_days": 10,
   "match_threshold": 0.12,
   "auto_match": true,
@@ -52,7 +52,7 @@
       ],
       "default_directory": "E:\\cfc",
       "fallback_model": "axonhub/deepseek",
-      "concurrency_limit": 1,
+      "concurrency_limit": 6,
       "branch_policy": "mainline"
     },
     {
@@ -64,7 +64,14 @@
         "/sc-data/cfc"
       ],
       "default_directory": "/sc-data/cfc",
-      "fallback_model": "axonhub/deepseek"
+      "fallback_model": "axonhub/deepseek",
+      "concurrency_limit": 4,
+      "model_chain": [
+        "opencode/deepseek-v4.1-flash-free",
+        "axonhub/deepseek",
+        "nvidia/nvidia/nemotron-3-ultra-550b-a55b",
+        "agnes/agnes-3.0-flash"
+      ]
     },
     {
       "name": "lan-204",
@@ -76,7 +83,11 @@
       ],
       "default_directory": "D:\\cfc",
       "fallback_model": "axonhub/deepseek",
-      "branch_policy": "mainline"
+      "concurrency_limit": 4,
+      "branch_policy": "mainline",
+      "dir_aliases": {
+        "/sc-data/cfc": "D:/cfc"
+      }
     },
     {
       "name": "lan-189",
@@ -88,6 +99,7 @@
       ],
       "default_directory": "C:\\code\\cfc",
       "fallback_model": "axon/deepseek",
+      "concurrency_limit": 4,
       "model_chain": [
         "opencode/deepseek-v4.1-flash-free",
         [
@@ -95,7 +107,10 @@
           "axon/deepseek"
         ],
         "nvidia/nvidia/nemotron-3-ultra-550b-a55b"
-      ]
+      ],
+      "dir_aliases": {
+        "/sc-data/cfc": "C:/code/cfc"
+      }
     },
     {
       "name": "prod-etotem",
@@ -110,7 +125,8 @@
       "danger": true,
       "readonly_default": true,
       "fallback_model": "axonhub/deepseek",
-      "manual_only": true
+      "concurrency_limit": 4,
+      "auto_prod": true
     },
     {
       "name": "pub-iwintrue",
@@ -122,9 +138,10 @@
         "/sc-data/caremate"
       ],
       "default_directory": "/sc-data/cfc",
-      "fallback_model": "etotem/deepseek"
+      "fallback_model": "etotem/deepseek",
+      "concurrency_limit": 6
     }
   ],
   "default_dispatch_model": "opencode/deepseek-v4.1-flash-free",
   "default_fallback_model": "axonhub/deepseek"
-}
+}