fix(bridge): ix_moe_bridge链接加--unresolved-symbols + probe脚本

ix_moe_bridge.so编译成功但加载时undefined symbol: silu_and_mul
原因：libixformer.so的符号在link time不可用
修复：-Wl,--unresolved-symbols=ignore-in-shared-libs
（和ix_unified_bridge.sh用的同一个方案）

运行时符号解析：ix_unified.py已有RTLD_GLOBAL preload逻辑

新增probe_all_so.py：在真机上探测12个.so的全部导出方法

ex_engine/precompile_ix_bridge.py

@@ -85,7 +85,7 @@ def main():
         logger.warning("This is expected if building outside the base image")
     
     # Build flags
-    extra_ldflags = []
+    extra_ldflags = ["-Wl,--unresolved-symbols=ignore-in-shared-libs"]
     for d in lib_dirs:
         extra_ldflags.extend([f"-L{d}", "-Wl,-rpath," + d])
     extra_ldflags.append("-lixformer")

probe_all_so.py

@@ -0,0 +1,52 @@
+"""在真机上运行：python3 probe_all_so.py
+输出每个.so的全部导出Python方法"""
+import importlib.util, os, sys
+
+SO_DIR = None
+for d in [
+    "/usr/local/corex/lib64/python3/dist-packages/vllm",
+    "/usr/local/corex/lib/python3/dist-packages/vllm",
+]:
+    if os.path.isfile(os.path.join(d, "corex_gdn_causal_conv.so")):
+        SO_DIR = d
+        break
+
+if not SO_DIR:
+    # try prebuilt
+    SO_DIR = os.path.join(os.path.dirname(__file__), 
+                          "qwen3_6_scripts/prebuilt/corex-3.2.3-ivcore10")
+
+ALL = [
+    "corex_gdn_causal_conv",
+    "corex_gdn_packed_decode",
+    "corex_gdn_beta_decay",
+    "corex_gdn_qk_map",
+    "corex_gdn_gated_norm",
+    "corex_attn_head_rms_norm",
+    "corex_paged_kv_gather",
+    "corex_fused_paged_prefill",
+    "corex_block_major_kv_transfer",
+    "corex_moe_direct_routed",
+    "corex_moe_exact_reduce",
+    "corex_moe_weight_gather",
+]
+
+for name in ALL:
+    so = os.path.join(SO_DIR, f"{name}.so")
+    if not os.path.isfile(so):
+        print(f"✗ {name}: NOT FOUND at {so}")
+        continue
+    try:
+        spec = importlib.util.spec_from_file_location(name, so)
+        mod = importlib.util.module_from_spec(spec)
+        spec.loader.exec_module(mod)
+        funcs = [x for x in dir(mod) if not x.startswith('_')]
+        print(f"✓ {name}: {funcs}")
+        # Try to get docstrings/signatures
+        for f in funcs:
+            obj = getattr(mod, f)
+            doc = getattr(obj, '__doc__', '')
+            if doc:
+                print(f"    {f}: {doc.strip()[:200]}")
+    except Exception as e:
+        print(f"✗ {name}: {e}")