web: package front into the wheel (splasher/web) + persist workspace layout

README.md

@@ -42,8 +42,8 @@ splasher/
              Returns a *semantic* ViewState (points + per-point labels + channel,
              BEV field, grid raster, selection, images) — not pixels.
   server/    FastAPI backend on the same Session + serves the web front; desktop app.
-web/         web front (vanilla, zero build) — the ONLY front.
-  vendor/    Three.js hosted locally (offline).
+  web/       web front (vanilla, zero build) — the ONLY front (packaged in the wheel).
+    vendor/  Three.js hosted locally (offline).
 ```
 
 **One front, one engine.** The web front is served by the backend; the desktop app
@@ -55,7 +55,7 @@ exposes `view_state()` + commands (`paint_rect`, `select_rect`, `apply_selection
 `set_frame`, `set_accum_radius`, `commit_grid`, `save`/`load`, …). Plugging in another front
 = consuming this `Session` (the web does it over HTTP). **Colorization stays on the front
 side**: each front draws the primitives its own way (reference helpers in
-`splasher.engine.render`, mirrored in JS under `web/src`).
+`splasher.engine.render`, mirrored in JS under `splasher/web/src`).
 
 ## Installation
 
@@ -84,7 +84,7 @@ Dark brutalist black-&-blue design. Labelable top-down (BEV) view (underlay mode
 height / density / intensity) + **3D/camera panels you can add, resize, and each bind to a
 channel** (3D color-by: height / intensity). Sensor placements (from `ChannelSpec.placement`)
 are drawn as markers in 3D. Classes are fully editable (⚙ in the *Classes* panel). Three.js
-is hosted locally (`web/vendor`) → works offline.
+is hosted locally (`splasher/web/vendor`) → works offline.
 
 > Native desktop window: the `app` extra ships a Qt WebEngine (Chromium) backend, so
 > `uv sync --extra app && splasher demo` opens a real native window out of the box. If no

splasher/server/app.py

@@ -15,8 +15,8 @@ from ..engine.session import Session
 from .files import combine_clouds, list_dir, open_file
 from .protocol import encode_array, grid_from_dict, session_info_to_dict, view_state_to_dict
 
-# Web front (vanilla, zero build) served as-is — `web/` directory at the repo root.
-WEB_DIR = Path(__file__).resolve().parents[2] / "web"
+# Web front (vanilla, zero build) served as-is — packaged at `splasher/web/`.
+WEB_DIR = Path(__file__).resolve().parents[1] / "web"
 
 
 def _as_session(session_or_source, labels) -> Session:

splasher/web/src/app.js

@@ -87,6 +87,9 @@ async function boot() {
   apply(first);
   fillGridForm(first.grid);
   updateDims(readGridForm());
+
+  await restoreWorkspace();                       // reopen views + restore layout from last session
+  window.addEventListener("beforeunload", saveWorkspace);
 }
 
 function apply(v) {
@@ -178,6 +181,44 @@ function updateSourceFromClouds() {
 function onFilesChanged() {
   if (fileMode) { buildClouds(); updateSourceFromClouds(); }
   renderOpenViews();
+  saveWorkspace();
+}
+
+// ------------------------------------------------------------- workspace persistence
+const WS_KEY = "splasher-workspace";
+function saveWorkspace() {
+  if (!manager) return;
+  try {
+    const grow = (sel) => parseFloat(getComputedStyle(document.querySelector(sel)).flexGrow) || 1;
+    localStorage.setItem(WS_KEY, JSON.stringify({
+      files: manager.openFiles().map((f) => f.path),
+      dir: fsPath,
+      layout: {
+        rail: document.querySelector(".rail").getBoundingClientRect().width,
+        bev: grow(".bev-panel"), views: grow(".views"),
+      },
+    }));
+  } catch { /* ignore */ }
+}
+async function restoreWorkspace() {
+  let ws;
+  try { ws = JSON.parse(localStorage.getItem(WS_KEY) || "null"); } catch { ws = null; }
+  if (!ws) return;
+  if (ws.dir) fsPath = ws.dir;
+  if (ws.layout) {
+    const L = ws.layout;
+    if (L.rail) document.querySelector(".rail").style.flex = `0 0 ${L.rail}px`;
+    if (L.bev) document.querySelector(".bev-panel").style.flexGrow = L.bev;
+    if (L.views) document.querySelector(".views").style.flexGrow = L.views;
+  }
+  if (fileMode && ws.files && ws.files.length) {
+    const cb = manager.onFiles; manager.onFiles = null;        // bulk: refresh once at the end
+    for (const path of ws.files) {
+      try { manager.addFile(await api.fsOpen(path)); } catch { /* file gone/changed */ }
+    }
+    manager.onFiles = cb;
+    onFilesChanged();
+  }
 }
 
 function buildAddBar() {