Add infrastructure for auto EP selection (#24430)

### Description
<!-- Describe your changes. -->
Add infrastructure to enable auto EP selection.

Device discovery for CPU/GPU/NPU on Windows.
Supports internal (CPU/DML/WebGPU) and provider bridge (CUDA) EPs
currently.
Infrastructure will be used with plugin EPs next.

Selection policy implementation will be added next, so in the interim
there's a temporary function with manually specified selection so unit
tests can cover the end-to-end.

### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->

---------

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Adrian Lizarraga <adlizarraga@microsoft.com>

Author: 3 people

cmake/onnxruntime_common.cmake

@@ -11,6 +11,8 @@ set(onnxruntime_common_src_patterns
     "${ONNXRUNTIME_ROOT}/core/common/logging/*.cc"
     "${ONNXRUNTIME_ROOT}/core/common/logging/sinks/*.h"
     "${ONNXRUNTIME_ROOT}/core/common/logging/sinks/*.cc"
+    "${ONNXRUNTIME_ROOT}/core/platform/device_discovery.h"
+    "${ONNXRUNTIME_ROOT}/core/platform/device_discovery.cc"
     "${ONNXRUNTIME_ROOT}/core/platform/env.h"
     "${ONNXRUNTIME_ROOT}/core/platform/env.cc"
     "${ONNXRUNTIME_ROOT}/core/platform/env_time.h"
@@ -157,6 +159,9 @@ if(APPLE)
   target_link_libraries(onnxruntime_common PRIVATE "-framework Foundation")
 endif()
 
+if(MSVC)
+  target_link_libraries(onnxruntime_common PRIVATE dxcore.lib)
+endif()
 
 if(MSVC)
   if(onnxruntime_target_platform STREQUAL "ARM64")
@@ -205,7 +210,6 @@ elseif(NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
   endif()
 endif()
 
-
 if (RISCV64 OR ARM64 OR ARM OR X86 OR X64 OR X86_64)
     # Link cpuinfo if supported
     # Using it mainly in ARM with Android.

cmake/onnxruntime_session.cmake

@@ -18,11 +18,17 @@ if (onnxruntime_ENABLE_TRAINING_APIS)
   list(APPEND onnxruntime_session_srcs ${training_api_srcs})
 endif()
 
-
+# disable for all minimal builds. enabling this pulls in all the provider bridge stuff,
+# which is not enabled for any minimal builds.
 if (onnxruntime_MINIMAL_BUILD)
+  file(GLOB autoep_srcs
+    "${ONNXRUNTIME_ROOT}/core/session/ep_*.*"
+  )
+
   set(onnxruntime_session_src_exclude
     "${ONNXRUNTIME_ROOT}/core/session/provider_bridge_ort.cc"
     "${ONNXRUNTIME_ROOT}/core/session/model_builder_c_api.cc"
+    ${autoep_srcs}
   )
 
   list(REMOVE_ITEM onnxruntime_session_srcs ${onnxruntime_session_src_exclude})