Merge pull request #383 from KevinGriffin-new/fix/pdf-export

Never fail silently on PDF export; add EXPORTPDF <path> (#369).

The export flow handed off to an async rfd save dialog and mapped a None
result straight to Task::none(). On Linux None also means the dialog never
opened (broken XDG portal / missing zenity), and rfd reports that only via
log, so PDF export could end in total silence. The dialog-None arms now
print a message pointing at EXPORTPDF <path>, and EXPORT/EXPORTPDF take an
optional path that exports straight to a file with no dialog — the
workaround where the native dialog can't open, and a headless entry point.

Conflict: the fix (display.rs, file.rs, mod.rs, COMMANDS.md) auto-merged;
only the additive test block in automation.rs conflicted. Resolved by
keeping main's tests and adding the two #369 tests.

# Conflicts:
#	src/app/automation.rs

src/app/commands/display.rs

@@ -365,8 +365,40 @@ impl OpenCADStudio {
             "PLOT" | "PRINT" => {
                 return Some(Task::done(Message::PlotDialogOpen));
             }
-            "EXPORT" | "EXPORTPDF" => {
-                return Some(Task::done(Message::PlotExport));
+            // With no argument these open the save dialog; with a path they
+            // export straight to it. The direct form is also the workaround for
+            // systems where the native save dialog cannot open at all (broken
+            // XDG portal / missing zenity on Linux) — there the dialog future
+            // resolves to None and no export would happen. (#369)
+            cmd if cmd == "EXPORT"
+                || cmd == "EXPORTPDF"
+                || cmd.starts_with("EXPORT ")
+                || cmd.starts_with("EXPORTPDF ") =>
+            {
+                // Strip the keyword actually typed — EXPORTPDF first, since
+                // EXPORT is its prefix (see #295 for the failure mode).
+                let arg = cmd
+                    .strip_prefix("EXPORTPDF")
+                    .or_else(|| cmd.strip_prefix("EXPORT"))
+                    .unwrap_or("")
+                    .trim()
+                    .trim_matches('"');
+                if arg.is_empty() {
+                    return Some(Task::done(Message::PlotExport));
+                }
+                let mut path = std::path::PathBuf::from(arg);
+                if path.extension().is_none() {
+                    path.set_extension("pdf");
+                }
+                // A bare filename lands next to the drawing when it has a home.
+                if path.is_relative() {
+                    if let Some(dir) =
+                        self.tabs[i].current_path.as_deref().and_then(|p| p.parent())
+                    {
+                        path = dir.join(path);
+                    }
+                }
+                return Some(self.on_plot_export_path_some(path));
             }
             // PLOTSTYLE — load or clear CTB/STB plot style table
             cmd if cmd == "PLOTSTYLE" || cmd.starts_with("PLOTSTYLE ") => {