Distribute prebuilt binaries via the npm registry #3750

- Remove all custom download logic for prebuilt binaries
- Add scripts to populate package contents
- Specify minimum versions of common package managers
- Remove sharp.vendor runtime API as no-longer relevant
- Update installation docs and issue templates

npm/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "@sharpen/sharp",
+  "version": "0.0.1-alpha.1",
+  "private": "true",
+  "workspaces": [
+    "darwin-x64",
+    "darwin-arm64",
+    "linux-arm",
+    "linux-arm64",
+    "linuxmusl-arm64",
+    "linuxmusl-x64",
+    "linux-x64",
+    "win32-ia32",
+    "win32-x64"
+  ]
+}