CAM routing refactor, area operation, and taper ball tool implementation

Major routing improvements:
- Refactor depth-first routing algorithm for better path optimization
- Reimplemented outline, roughing, pocket, and trace as area operation wrappers
- Add pocket shadow travel routing with optimized descent using travel bounds
- Improve contour routing with arc detection and polyEmit arc strategy
- Add area smoothing and ease-down options
- Fix outline handling with thru holes and surface reversal on tip2tip
- Move widget shadow methods into widget class for faster hole detection
- Better camInnerFirst support and proper feed/plunge defaults

Tool system improvements:
- Implement taper ball tool type with full support
- Add renderTool2() for profile-based visualization
- Convert tool menu to init code with bound vars
- Fix auto tool and auto spindle for prep operations
- Update tool profile generation for taperball geometry
- Add calcTaperBallExtent() for proper ball tangency calculations

Code cleanup:
- Remove duplicated slicer code from specialized slicers
- Asyncify shadowAt operations
- Deprecate pocket engrave operation
- Simplify upNover implementation
- Fix animation with new tool+settings requirements

src/kiri/mode/cam/anim-3d-be.js

@@ -12,6 +12,7 @@ let nextMeshID = 1,
     tool,
     tools,
     last,
+    settings,
     stockZ,
     stockIndexMsg = false,
     stockSlices,
@@ -34,10 +35,10 @@ export function init(worker) {
     const { dispatch } = worker;
 
     dispatch.animate_setup2 = function (data, send) {
-        const { settings } = data;
+        settings = data.settings;
+
         const { controller, process } = settings;
-        const print = worker.current.print;
-        const density = parseInt(settings.controller.animesh) * 1000;
+        const { print } = worker.current;
         const isIndexed = process.camStockIndexed;
 
         pathIndex = 0;
@@ -141,7 +142,7 @@ function renderPath(send) {
     }
 
     const id = toolID;
-    const rezstep = Math.min(tool.maxDiameter(), 1) / 4;
+    const rezstep = tool ? Math.min(tool.maxDiameter(), 1) / 4 : 1;
     // console.log({ rezstep });
 
     if (last) {
@@ -273,7 +274,7 @@ function toolUpdate(toolid, send) {
     if (tool) {
         send.data({ mesh_del: toolID });
     }
-    tool = new Tool({ tools }, toolid);
+    tool = new Tool(settings, toolid);
     const Instance = CSG.Instance();
     const slen = tool.shaftLength() || 15;
     const srad = tool.shaftDiameter() / 2;
@@ -286,6 +287,16 @@ function toolUpdate(toolid, send) {
         mesh = cylinder(tlen - frad * 2, frad, frad, 20, true)
             .add(sphere(frad, 20).translate(0, 0, -(tlen - frad * 2) / 2))
             .add(cylinder(slen, srad, srad, 20, true).translate(0, 0, flen / 2));
+    } else if (tool.isTaperBall()) {
+        const trad = Math.max(tool.tipDiameter() / 2, 0.001);
+        const brad = trad; // ball radius equals tip radius
+        const taperLen = flen - brad; // taper length excludes ball
+        // shaft at top
+        mesh = cylinder(slen, srad, srad, 20, true).translate(0, 0, slen / 2)
+            // taper cone in middle
+            .add(cylinder(taperLen, trad, frad, 20, true).translate(0, 0, -taperLen / 2))
+            // ball at bottom
+            .add(sphere(brad, 20).translate(0, 0, -(taperLen + brad)));
     } else if (tool.isTaperMill()) {
         const trad = Math.max(tool.tipDiameter() / 2, 0.001);
         mesh = cylinder(slen, srad, srad, 20, true).translate(0, 0, slen / 2)