UI.9: share docking transactions and preserve viewer lifecycle

Preserve legacy selection repair, modifier routing, viewer lifecycle and workspace persistence through the shared docking integration. Qualify the complete workspace gate by refreshing the 18 stale Audio Spectrum hashes for the existing linear renderer, with an independent synthetic-tone regression.

docs/control-protocol.md

@@ -53,7 +53,7 @@ panel registers an element id; both are enforced by `crates/ui-egui/tests/ui_age
 
 | Method | Params | Result |
 |---|---|---|
-| `ui.inspect` | `{}` | Window size, pixels per point, fps, serialized `UiState`, playback, time, active comp, selection, open dialog, last render ms. |
+| `ui.inspect` | `{}` | Window size, pixels per point, fps, serialized `UiState`, playback, time, active comp, selection, open dialog, last render ms, `keyboardFocus`, `windowFocused`, `workspaceStorageError`. |
 | `ui.elements` | `{prefix?}` | `[{id, label, rect: [x, y, w, h]}]`: the widgets drawn in the last frame, in points. |
 | `ui.set` | `{tool?, workspace?, theme?, focused?, viewer?, timeline?, menuBar?, home?}` | `viewer: {zoom (null = fit), res: Full\|Half\|Third\|Quarter\|Auto, pan: [x,y], grid, rulers, safeMargins, transparencyGrid}`; `timeline: {pps (null = fit), start, graphEditor, showModes, openLayers: [ids], openGroups: [uids]}`. |
 | `ui.panel.show` / `ui.panel.close` | `{panel}` | Panels: `Project`, `Composition`, `Timeline`, `EffectControls`, `EffectsPresets`, `Info`, `Preview`, `Character`, `Paragraph`, `Align` and others. |
@@ -62,6 +62,26 @@ panel registers an element id; both are enforced by `crates/ui-egui/tests/ui_age
 | `ui.focus` | `{}` | Activates the window and takes keyboard focus. Agents normally avoid this, because the app is started without stealing focus. |
 | `app.quit` | `{force?}` | Closes the app. A modified project shows the Save / Don't Save / Cancel prompt first (automation ids `dialog.unsaved.save`, `dialog.unsaved.dontSave`, `dialog.unsaved.cancel`) unless `force: true`. |
 
+`keyboardFocus` is `null` when no egui widget has keyboard focus. Otherwise it contains the
+actual widget `id` (hexadecimal), its `rect: [x, y, w, h]` when available, an `automationId`
+when the widget registered its response identity, and `registryCandidates` containing exact
+rectangle matches. Candidates alone do not establish widget identity. Header, toolbar and
+dock-tab controls register their response identity. `ui.focused` continues to identify the
+focused panel; it is separate from keyboard widget focus. `windowFocused` reports the native
+window focus received by egui, which can differ from the retained widget focus.
+
+When a configuration store is available, current dock and floating geometry, focused and
+maximized panels, and named workspace snapshots persist in `workspaces.json`. The current
+layout and named snapshots are independent: changing a divider does not overwrite the named
+snapshot until `window.saveWorkspace` runs. Changes save after pointer release, at most once
+per second, with a final save on normal exit. Version 1 files are limited to 1 MiB and bounded
+workspace trees; extra viewer IDs must be between 1 and 65,535. Native reads enforce the size
+limit while reading and report I/O and UTF-8
+errors. Unreadable, invalid or newer files leave the default workspace available and are
+preserved for the entire session, including after later layout changes. Load and save errors
+appear in the status message and the nullable
+`workspaceStorageError` field; a failed write remains eligible for retry.
+
 ## Input
 
 Points are logical window coordinates. A target is `{id}` (the element's centre; add `fx`/`fy` between
@@ -141,3 +161,21 @@ including outside the layer's `[in, out)` range. Timing metadata carries outside
 `keys.set` and `prop.get.keys[]` report both bases and warnings without an explicit base too.
 `prop.get.time` is comp seconds. For these commands, `path` or `prop` identifies a property, not a group.
 Set a layer's offset with `layer.timing {layer, start}` (comp seconds).
+
+Panel moves, tab ordering, edge splits and floating geometry use shared docking transactions.
+`window.floatPanel` requires exactly four finite numbers when `rect` is supplied. Invalid
+geometry or missing source/anchor panels leaves the layout unchanged. The persisted workspace
+shape is unchanged: accordion open states and explicit heights, floating groups, and dynamic
+viewer/ScriptUI identities remain app data. Pointer drops use the same shared placement rules
+as commands, with floating groups resolved in their actual window stacking order.
+
+`window.dockAction` accepts `{action}` using the shared docking action's JSON form. It
+covers tab moves and ordering, split and floating geometry, activation, and closing.
+For example, `{"action":{"ResizeSplit":{"path":[],"size":{"FixedFirst":360}}}}`
+resizes the root split; path entries use `false` for the first child and `true` for
+the second. `{"action":{"MoveFloating":{"panel":"Info","rect":[45,65,420,320]}}}`
+repositions and resizes the floating group containing Info. Invalid actions leave the
+layout unchanged. Pointer gestures dispatch through this same catalog command.
+EffectCraft also supports `SetStackOpen` and `ResizeStack`. Dynamic panel identities use
+`{"Viewer":42}` or `{"ScriptPanel":77}` in the action. Closing runs the existing viewer
+and ScriptUI lifecycle callbacks; opening uses the existing panel creation commands.