Live mod options: overrides end with their session's plan

Review (#602): live_option_values() was process-static and never cleared, so
an override set in one session outlived mod_runtime_initialize and a new
committed plan (committed 'eight', API still answered the old 'four'). Every
plan change -- initialise, commit, the netplay plan (vanilla or negotiated)
-- now drops the overrides. test_mod_runtime: a second session answers its
own committed value.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

runtime/src/mod_runtime.cpp

@@ -1462,6 +1462,12 @@ bool mod_runtime_netplay_content_negotiation() {
     return netplay_content_negotiation_enabled;
 }
 
+/* Live option overrides (psx_mod_set_option_live) belong to one session's
+ * plan: initialising the runtime, committing a plan or switching to the
+ * netplay plan drops them, so a new plan's committed values are what the
+ * API answers (defined with the overrides below). */
+void reset_live_option_overrides();
+
 bool mod_runtime_initialize(const std::filesystem::path& root,
                             const std::string& game_id,
                             uint32_t game_entry_pc,
@@ -1480,6 +1486,7 @@ bool mod_runtime_initialize(const std::filesystem::path& root,
     s.audio_tracks.clear();
     s.extent_start = 0;
     s.plan = {};
+    reset_live_option_overrides();  /* a new plan ends the last session's live values */
     s.validation = {};
     s.raw_disc_index.clear();
     s.user_disc_index.clear();
@@ -1586,6 +1593,7 @@ bool mod_runtime_clear_for_netplay(std::string* error) {
     s.audio_tracks.clear();
     s.extent_start = 0;
     s.plan = {};
+    reset_live_option_overrides();  /* a new plan ends the last session's live values */
     s.validation = {};
     s.raw_disc_index.clear();
     s.user_disc_index.clear();
@@ -1740,6 +1748,7 @@ bool mod_runtime_commit_netplay(const std::filesystem::path& disc_path,
     if (renderer) plan.plugins.push_back({renderer, "", ""});
     s.disc_path = disc_path;
     s.plan = std::move(plan);
+    reset_live_option_overrides();  /* a new plan ends the last session's live values */
     mod_runtime_set_session_plan_fp({});
     psx_mod_netplay_set_active(1);
     std::fprintf(stdout, "psxrecomp: title netplay profile %s (%s)\n",
@@ -2067,6 +2076,7 @@ static bool install_plan(RuntimeMods& s, ModResolution plan,
     s.audio_tracks.clear();
     s.extent_start = 0;
     s.plan = std::move(plan);
+    reset_live_option_overrides();  /* a new plan ends the last session's live values */
     {
         HostLaunchTimingScope index_timing(HOST_LAUNCH_BUILD_DISC_INDEX);
         build_disc_index(s);
@@ -2870,6 +2880,10 @@ extern "C" int psx_mod_save_selection(void) {
     return 1;
 }
 
+namespace PSXRecompV4 {
+void reset_live_option_overrides() { live_option_values().clear(); }
+}  // namespace PSXRecompV4
+
 extern "C" int psx_mod_set_option_live(const char* package_id, const char* feature_id,
                                        const char* option_id, const char* value) {
     using namespace PSXRecompV4;

runtime/tests/test_mod_runtime.cpp

@@ -1124,6 +1124,17 @@ int main(int argc, char** argv) {
                   std::string(value) == "four",
               "a refused live set must not change the value later reads see");
         option_changed_refuse = 0;
+        /* A new session (initialise + commit) answers its own committed
+         * plan, not the previous session's live override. */
+        check(PSXRecompV4::mod_runtime_initialize(
+                  req_root, "SLUS-REQ", 0x80002000, {}, &error),
+              error.c_str());
+        check(PSXRecompV4::mod_runtime_commit(stock_path, &error),
+              "the second session must commit");
+        mod_runtime_activate_plugins();
+        check(psx_mod_option_value("runtime.ram", "big-ram", "size", value, sizeof(value)) == 1 &&
+                  std::string(value) == "eight",
+              "a live override must not outlive its session's plan");
         check(psx_mod_set_option_live("runtime.ram", "no-such-feature", "size", "x") == 0,
               "features outside the plan are not live-settable");
         check(psx_mod_save_selection() == 1, "saving the selection mid-session must succeed");