fix(i2p): Windows link order — i2pd archives + Boost/zlib sandwich

The linker needs to see i2pd archives, then Boost/zlib to resolve
their symbols, then i2pd archives AGAIN to resolve any remaining
references. Added raw -l fallbacks for MinGW where Boost:: CMake
imported targets may not exist even though libs are installed.

src/CMakeLists.txt

@@ -234,31 +234,50 @@ if(USE_I2P_EMBEDDED)
     )
     # i2pd builds as two static libraries: libi2pd.a (core router) and
     # libi2pd_client.a (SAM, SOCKS, tunnels, client context). Both are needed.
-    # The static libs have circular inter-dependencies. Rather than using
-    # --start-group/--end-group (which CMake mis-orders with Ninja), we
-    # list each archive twice so the linker resolves all symbols in two
-    # left-to-right passes.
+    # The static libs have circular inter-dependencies and also reference
+    # Boost (filesystem, program_options) and zlib symbols. On MinGW the
+    # Boost:: targets may not exist as CMake imported targets even though
+    # the libraries are installed, so we use raw -l flags as a fallback.
     target_link_libraries(triangles_common PUBLIC
         "${I2P_SOURCE_ROOT}/libi2pdclient.a"
         "${I2P_SOURCE_ROOT}/libi2pd.a"
         "${I2P_SOURCE_ROOT}/libi2pdlang.a"
         "${I2P_SOURCE_ROOT}/libi2pdclient.a"
         "${I2P_SOURCE_ROOT}/libi2pd.a"
-        Boost::program_options Boost::thread Boost::chrono
+    )
+    # Boost and zlib dependencies of i2pd — these MUST come after the
+    # archives in link order so unresolved symbols get satisfied.
+    if(TARGET Boost::filesystem)
+        target_link_libraries(triangles_common PUBLIC Boost::filesystem)
+    elseif(WIN32)
+        target_link_libraries(triangles_common PUBLIC boost_filesystem-mt)
+    endif()
+    if(TARGET Boost::system)
+        target_link_libraries(triangles_common PUBLIC Boost::system)
+    elseif(WIN32)
+        target_link_libraries(triangles_common PUBLIC boost_system-mt)
+    endif()
+    if(TARGET Boost::program_options)
+        target_link_libraries(triangles_common PUBLIC Boost::program_options)
+    elseif(WIN32)
+        target_link_libraries(triangles_common PUBLIC boost_program_options-mt)
+    endif()
+    target_link_libraries(triangles_common PUBLIC
+        Boost::thread Boost::chrono
         OpenSSL::SSL OpenSSL::Crypto
         ZLIB::ZLIB
     )
+    # List the archives again after Boost/zlib so the linker can resolve
+    # any remaining i2pd→Boost references in a second pass.
+    target_link_libraries(triangles_common PUBLIC
+        "${I2P_SOURCE_ROOT}/libi2pd.a"
+        "${I2P_SOURCE_ROOT}/libi2pdclient.a"
+    )
     if(WIN32)
         target_link_libraries(triangles_common PUBLIC
             -Wl,--allow-multiple-definition
         )
     endif()
-    if(TARGET Boost::filesystem)
-        target_link_libraries(triangles_common PUBLIC Boost::filesystem)
-    endif()
-    if(TARGET Boost::system)
-        target_link_libraries(triangles_common PUBLIC Boost::system)
-    endif()
 endif()
 
 # Platform-specific libraries