feat: Support socket path of KPXC 2.7.4 Flatpak

To avoiding mounting everything into Flatpak sandbox, the socket was
moved into a separate path under Linux [1][2].

Note this does not affect other distributions under Linux as there is a
symbolic link from the old path [3].

[1] keepassxreboot/keepassxc#8030
[2] keepassxreboot/keepassxc@1009650
[3] https://github.com/keepassxreboot/keepassxc/blob/2.7.4/src/browser/BrowserShared.cpp#L49

src/utils/socket.rs

@@ -22,6 +22,7 @@ pub fn get_socket_path() -> Result<PathBuf> {
         Box::new(LinuxSocketPath260),
         Box::new(MacSocketPath260),
         Box::new(WindowsSocketPath260),
+        Box::new(LinuxSocketPath274),
         Box::new(WindowsSocketPath262),
         Box::new(WindowsSocketPathNatMsg),
     ];
@@ -97,6 +98,33 @@ impl SocketPath for LinuxSocketPath260 {
     }
 }
 
+// https://github.com/keepassxreboot/keepassxc/commit/1009650b5c2697f5420c0f4398271652a4158c1a
+struct LinuxSocketPath274;
+impl SocketPath for LinuxSocketPath274 {
+    fn get_path(&self) -> Result<PathBuf> {
+        let base_dirs = directories_next::BaseDirs::new()
+            .ok_or_else(|| anyhow!("Failed to initialise base_dirs"))?;
+        let result = base_dirs
+            .runtime_dir()
+            .ok_or_else(|| anyhow!("Failed to locate runtime_dir automatically"))?
+            .join("app")
+            .join("org.keepassxc.KeePassXC")
+            .join(KEEPASS_SOCKET_NAME);
+        if result.exists() {
+            Ok(result)
+        } else {
+            Err(anyhow!(io::Error::new(
+                io::ErrorKind::NotFound,
+                format!("{} does not exist", result.to_string_lossy()),
+            )))
+        }
+    }
+
+    fn matches_os(&self) -> bool {
+        cfg!(target_os = "linux")
+    }
+}
+
 struct MacSocketPathLegacy;
 impl SocketPath for MacSocketPathLegacy {
     fn get_path(&self) -> Result<PathBuf> {