Fix Windows CI compiler heap exhaustion by splitting interactions.cpp

Split tests/server/interactions.cpp (5,548 lines, 193KB) into 3 smaller
files to avoid MSVC C1060 "compiler is out of heap space" error on GitHub
Actions Windows CI.

Issue: Windows CI failed at interactions.cpp:2307 with C1060 during both
Debug and Release builds. The file was too large for MSVC to compile in
CI's constrained environment, despite compiling fine locally with the same
compiler version (MSVC 14.44.35207).

Solution: Split into 3 parts following the same pattern as commit 54dc027
which explicitly "split large test files for maintainability":

- interactions_part1.cpp (55 tests, 1,989 lines) - Core Tools/Resources/Prompts
- interactions_part2.cpp (59 tests, 2,104 lines) - Data types/Validation
- interactions_part3.cpp (50 tests, 1,741 lines) - Server capabilities/Notifications

All 164 tests accounted for and passing locally (3/3 tests, 0.04s).

Related: PR #11 (43e5e64) which introduced the large interactions.cpp file.
This change maintains all test coverage while fixing Windows CI builds.

Author: 0xeb

CMakeLists.txt

@@ -229,9 +229,18 @@ if(FASTMCPP_BUILD_TESTS)
   target_link_libraries(fastmcpp_server_patterns PRIVATE fastmcpp_core)
   add_test(NAME fastmcpp_server_patterns COMMAND fastmcpp_server_patterns)
 
-  add_executable(fastmcpp_server_interactions tests/server/interactions.cpp)
-  target_link_libraries(fastmcpp_server_interactions PRIVATE fastmcpp_core)
-  add_test(NAME fastmcpp_server_interactions COMMAND fastmcpp_server_interactions)
+  # Split into 3 parts to avoid MSVC heap exhaustion on CI (C1060)
+  add_executable(fastmcpp_server_interactions_part1 tests/server/interactions_part1.cpp)
+  target_link_libraries(fastmcpp_server_interactions_part1 PRIVATE fastmcpp_core)
+  add_test(NAME fastmcpp_server_interactions_part1 COMMAND fastmcpp_server_interactions_part1)
+
+  add_executable(fastmcpp_server_interactions_part2 tests/server/interactions_part2.cpp)
+  target_link_libraries(fastmcpp_server_interactions_part2 PRIVATE fastmcpp_core)
+  add_test(NAME fastmcpp_server_interactions_part2 COMMAND fastmcpp_server_interactions_part2)
+
+  add_executable(fastmcpp_server_interactions_part3 tests/server/interactions_part3.cpp)
+  target_link_libraries(fastmcpp_server_interactions_part3 PRIVATE fastmcpp_core)
+  add_test(NAME fastmcpp_server_interactions_part3 COMMAND fastmcpp_server_interactions_part3)
 
   add_executable(fastmcpp_server_context_meta tests/server/context_meta.cpp)
   target_link_libraries(fastmcpp_server_context_meta PRIVATE fastmcpp_core)