use per-user runtime stats path for reliable gsfd+tui updates

README.md

@@ -73,7 +73,7 @@ Default config path:
 
 Default speed stats path:
 - `$XDG_RUNTIME_DIR/gsf-speed.txt` (if available)
-- fallback `~/.local/state/gsf/speed.txt`
+- fallback `/tmp/gsf-speed.txt`
 - override with `GSF_STATS_PATH`
 
 ## runtime requirements

crates/core/src/inputspeed.rs

@@ -44,6 +44,11 @@ fn stats_path() -> PathBuf {
         return PathBuf::from(path);
     }
 
-    // Keep default shared across sudo/non-sudo runs.
+    if let Ok(runtime_dir) = std::env::var("XDG_RUNTIME_DIR")
+        && !runtime_dir.is_empty()
+    {
+        return PathBuf::from(runtime_dir).join("gsf-speed.txt");
+    }
+
     PathBuf::from("/tmp/gsf-speed.txt")
 }

daemon/src/main.rs

@@ -367,6 +367,11 @@ fn stats_path() -> PathBuf {
         return PathBuf::from(path);
     }
 
-    // Keep default shared across sudo/non-sudo runs.
+    if let Ok(runtime_dir) = std::env::var("XDG_RUNTIME_DIR")
+        && !runtime_dir.is_empty()
+    {
+        return PathBuf::from(runtime_dir).join("gsf-speed.txt");
+    }
+
     PathBuf::from("/tmp/gsf-speed.txt")
 }

nix/module.nix

@@ -89,6 +89,7 @@ in
       wantedBy = ["default.target"];
       after = ["graphical-session.target"];
       serviceConfig = {
+        Environment = ["GSF_STATS_PATH=%t/gsf-speed.txt"];
         ExecStart = "${cfg.package}/bin/gsfd --device ${lib.escapeShellArg cfg.device}${lib.optionalString (cfg.extraArgs != []) " ${extraArgs}"}";
         Restart = "on-failure";
         RestartSec = 1;