web: raster images, WBLOCK/SAVEALL/SCRIPT/CTB/LAYTRANS/INSERT, filled TTF text

A fresh web-vs-desktop audit found the remaining gaps; this closes the
top ten.

Raster images: IMAGE attach read the picked file via image::open on a
name-only path (dead on wasm), and raster references inside opened
drawings decoded the same way. Picked bytes are now registered in a
name-keyed store (the PDF-underlay pattern), decoding runs from memory,
and dropped .png/.jpg/.bmp/.tif files register by name so unresolved
references in opened drawings re-resolve and render (and export to PDF).

Command gaps fixed with the bytes-at-pick / download_bytes pattern:
- WBLOCK now downloads the extracted block instead of failing on fs.
- SAVEALL saves every dirty tab instead of printing a no-op message.
- SCRIPT picks and reads the .scr file through the browser picker.
- CENTERLTYPEFILE picks the .lin/.dnl file and populates from text.
- Custom .ctb tables picked on web now parse, register for the
  session, appear in the plot dialog list, and apply (load_named
  previously returned builtin-only on wasm).
- LAYTRANS 'Load standards file' parses the picked drawing on the
  existing web worker.
- INSERT 'from file' in the block palette parses picked bytes and
  feeds the shared import path.

Text fidelity: TTF-named styles rendered as thin stroke glyphs on web
because the font database was empty. Fetched Noto faces are now
registered into it with a family alias table (Arial, Times New Roman,
Cambria, ... -> Noto Sans/Serif), so those styles render filled, shape,
export to PDF as vector fills, and appear in the style picker.
ViewCube labels request semibold again on web.

docs/native-vs-web.md: the hatch and font rows were stale (both work on
web now), the GPU row claimed WebGPU is used where available (the
backend is pinned to OpenGL), and the parallelism row missed the parse
worker — all corrected.

(cherry picked from commit c643a10e)

Ported onto main (#1717 review): conflicts resolved toward main — the
font-file lookup, PDF searchable text, purge service, block palette and
plot-style copy stay as they are on main; the web pieces (font registry
and aliases, session plot styles, SCRIPT/SAVEALL/CENTERLTYPEFILE picks,
block-from-file on the web) are layered on top.

src/app/update/file.rs

@@ -2298,12 +2298,95 @@ impl OpenCADStudio {
                     crate::modules::insert::wblock::extract_block_to_doc(&document, &worker_name)
                 }
                 .map_err(|e| e.to_string())?;
-                crate::io::save(&document, &worker_path).map_err(|e| e.to_string())
+                #[cfg(not(target_arch = "wasm32"))]
+                {
+                    crate::io::save(&document, &worker_path).map_err(|e| e.to_string())
+                }
+                // Web: no filesystem behind the name-only path — serialize to
+                // bytes (the same document version `save` would pick, format
+                // from the chosen file name) and hand the browser a download,
+                // the way the other web exports do.
+                #[cfg(target_arch = "wasm32")]
+                {
+                    let ext = worker_path
+                        .extension()
+                        .map(|ext| ext.to_string_lossy().into_owned())
+                        .unwrap_or_else(|| "dwg".to_string());
+                    let bytes = crate::io::save_to_bytes(&document, &ext, document.version)?;
+                    let name = worker_path
+                        .file_name()
+                        .map(|n| n.to_string_lossy().into_owned())
+                        .unwrap_or_else(|| "block.dwg".into());
+                    crate::sys::download_bytes(&name, &bytes);
+                    Ok(())
+                }
             },
             move |result| Message::WblockWriteFinished(block_name, path, result),
         )
     }
 
+    /// Web SAVEALL: every dirty tab that already has a name-only path is
+    /// serialized and downloaded in one pass — the same
+    /// `save_to_bytes` + `download_bytes` route a single Save takes. The
+    /// browser may ask once for permission to download several files, which
+    /// is the platform's price. Clean tabs are skipped (re-downloading
+    /// identical bytes is noise); tabs with no path still need SAVEAS.
+    #[cfg(target_arch = "wasm32")]
+    pub(in crate::app) fn saveall_web(&mut self) {
+        let mut saved = 0usize;
+        let mut skipped = 0usize;
+        for t in 0..self.tabs.len() {
+            if self.tabs[t].is_start {
+                continue;
+            }
+            let Some(path) = self.tabs[t].current_path.clone() else {
+                skipped += 1;
+                continue;
+            };
+            if !self.tabs[t].dirty {
+                continue;
+            }
+            // The same preparation a single web Save makes on the tab.
+            self.sync_view_state_for_save(t);
+            sync_annotation_scale_header(&mut self.tabs[t].scene);
+            self.stamp_header_sysvars(t);
+            self.sync_solid_models_for_save(t);
+            self.tabs[t].scene.sync_native_parametric_graph();
+            let ext = path
+                .extension()
+                .map(|ext| ext.to_string_lossy().into_owned())
+                .unwrap_or_else(|| "dwg".to_string());
+            let version = self.tabs[t].scene.document.version;
+            let filename = path
+                .file_name()
+                .map(|name| name.to_string_lossy().into_owned())
+                .unwrap_or_else(|| path.to_string_lossy().into_owned());
+            match crate::io::save_to_bytes(&self.tabs[t].scene.document, &ext, version) {
+                Ok(bytes) => {
+                    crate::sys::download_bytes(&filename, &bytes);
+                    self.tabs[t].scene.document.version = version;
+                    self.tabs[t].dirty = false;
+                    self.tabs[t].recovery_save_as_required = false;
+                    saved += 1;
+                }
+                Err(error) => self
+                    .command_line
+                    .push_error(crate::tf!("SAVEALL: {} failed: {error}", path.display()).as_ref()),
+            }
+        }
+        self.command_line.push_output(
+            crate::tf!(
+                "SAVEALL: saved {saved} drawing(s){}.",
+                if skipped > 0 {
+                    crate::tf!("; {skipped} need SAVEAS (no file path yet)").into_owned()
+                } else {
+                    String::new()
+                }
+            )
+            .as_ref(),
+        );
+    }
+
     pub(super) fn on_stl_export_path_some(&mut self, path: std::path::PathBuf) -> Task<Message> {
         // Re-build STL bytes (we can't easily pass them through the message).
         let i = self.active_tab;
@@ -3538,9 +3621,7 @@ impl OpenCADStudio {
     /// single derivation every web snapshot/remove site must agree on, or a
     /// remove misses the snapshot a round wrote (and vice versa).
     #[cfg(target_arch = "wasm32")]
-    pub(super) fn web_autosave_key(
-        tab: &crate::app::document::DocumentTab,
-    ) -> String {
+    pub(super) fn web_autosave_key(tab: &crate::app::document::DocumentTab) -> String {
         tab.current_path
             .as_ref()
             .and_then(|path| path.file_name())
@@ -3784,10 +3865,8 @@ impl OpenCADStudio {
                 // survives in OPFS and is re-offered on the next boot.
                 if !crate::io::web_drop::enqueue_restore(open_name, bytes, key) {
                     self.command_line.push_warning(
-                        crate::tf!(
-                            "Autosave copy could not be queued: too many pending opens"
-                        )
-                        .as_ref(),
+                        crate::tf!("Autosave copy could not be queued: too many pending opens")
+                            .as_ref(),
                     );
                     self.queue_next_web_autosave_prompt();
                 }