docs(spark_web): update README with implemented but undocumented APIs

Mark Notification, Blob/File/FileList, CanvasRenderingContext2D,
TextMetrics, and ImageData as Done (were incorrectly listed as TODO).
Add missing files to the architecture diagram (canvas, file,
geolocation, notification, permissions). Expand notes for Geolocation,
Permissions, Event, and MouseEvent with previously unlisted properties.

Author: kevin-sakemaer

packages/spark_web/README.md

@@ -84,18 +84,33 @@ spark_web/lib/
     ├── dom.dart                # Element, HTMLElement, Document, ShadowRoot, Text, Comment
     ├── collections.dart        # DOMTokenList, NamedNodeMap, Attr
     ├── css.dart                # CSSStyleSheet, CSSStyleDeclaration
+    ├── canvas.dart             # CanvasRenderingContext2D, TextMetrics, ImageData
+    ├── file.dart               # Blob, File, FileList
+    ├── geolocation.dart        # Geolocation, GeolocationPosition, GeolocationCoordinates
+    ├── notification.dart       # Notification, NotificationOptions, NotificationAction
+    ├── permissions.dart        # Permissions, PermissionStatus, PermissionDescriptor
     ├── window.dart             # Window, Storage, Location, History, Navigator, Console, ...
     ├── server/                 # Server implementations (no-ops / Dart-native fallbacks)
     │   ├── factory.dart
     │   ├── dom.dart
     │   ├── collections.dart
     │   ├── css.dart
+    │   ├── canvas.dart
+    │   ├── file.dart
+    │   ├── geolocation.dart
+    │   ├── notification.dart
+    │   ├── permissions.dart
     │   └── window.dart
     └── browser/                # Browser implementations (wrap package:web)
         ├── factory.dart
         ├── dom.dart
         ├── collections.dart
         ├── css.dart
+        ├── canvas.dart
+        ├── file.dart
+        ├── geolocation.dart
+        ├── notification.dart
+        ├── permissions.dart
         └── window.dart
 ```
 
@@ -108,8 +123,8 @@ The table below tracks what percentage of the [MDN Web API](https://developer.mo
 | API | Status | Notes |
 |-----|--------|-------|
 | `EventTarget` | ✅ Done | `addEventListener`, `removeEventListener`, `dispatchEvent` |
-| `Event` | ✅ Done | `type`, `target`, `currentTarget`, `preventDefault`, `stopPropagation` |
-| `MouseEvent` | ✅ Done | `clientX/Y`, `pageX/Y`, `screenX/Y`, `button`, modifier keys |
+| `Event` | ✅ Done | `type`, `target`, `currentTarget`, `bubbles`, `cancelable`, `preventDefault`, `stopPropagation`, `stopImmediatePropagation` |
+| `MouseEvent` | ✅ Done | `clientX/Y`, `pageX/Y`, `screenX/Y`, `button`, `buttons`, modifier keys |
 | `KeyboardEvent` | ✅ Done | `key`, `code`, `repeat`, `location`, modifier keys |
 | `InputEvent` | ✅ Done | `data`, `inputType`, `isComposing` |
 | `FocusEvent` | ✅ Done | `relatedTarget` |
@@ -243,8 +258,9 @@ The table below tracks what percentage of the [MDN Web API](https://developer.mo
 | `EventSource` | ❌ TODO | Server-sent events |
 | `XMLHttpRequest` | ❌ TODO | Legacy — consider skipping |
 | `FormData` | ❌ TODO | `append`, `get`, `set`, `entries` |
-| `Blob` | ❌ TODO | `size`, `type`, `text()`, `arrayBuffer()`, `slice()` |
-| `File` | ❌ TODO | `name`, `lastModified`, `size`, `type` |
+| `Blob` | ✅ Done | `size`, `type`, `text()`, `arrayBuffer()`, `slice()`, `stream()` |
+| `File` | ✅ Done | `name`, `lastModified` (extends Blob) |
+| `FileList` | ✅ Done | `length`, `item()` |
 | `FileReader` | ❌ TODO | `readAsText()`, `readAsDataURL()`, `result` |
 
 ### Observers
@@ -260,9 +276,10 @@ The table below tracks what percentage of the [MDN Web API](https://developer.mo
 
 | API | Status | Notes |
 |-----|--------|-------|
-| `CanvasRenderingContext2D` | ❌ TODO | Drawing primitives |
+| `CanvasRenderingContext2D` | ✅ Done | Full 2D drawing: rect, path, arc, bezier, text, image, pixel manipulation, transforms, state save/restore, line dash, compositing |
+| `TextMetrics` | ✅ Done | `width`, `actualBoundingBoxLeft/Right/Ascent/Descent`, `fontBoundingBoxAscent/Descent` |
+| `ImageData` | ✅ Done | `width`, `height`, `data` |
 | `OffscreenCanvas` | ❌ TODO | |
-| `ImageData` | ❌ TODO | |
 | `Path2D` | ❌ TODO | |
 | `WebGLRenderingContext` | ❌ TODO | Consider out of scope |
 | `WebGL2RenderingContext` | ❌ TODO | Consider out of scope |
@@ -309,9 +326,9 @@ The table below tracks what percentage of the [MDN Web API](https://developer.mo
 | `TextDecoder` | ❌ TODO | `decode()` |
 | `structuredClone()` | ❌ TODO | |
 | `queueMicrotask()` | ❌ TODO | |
-| `Notification` | ❌ TODO | |
-| `Geolocation` | ✅ Done | |
-| `Permissions` | ✅ Done | `query()`, `PermissionStatus`, `PermissionDescriptor` |
+| `Notification` | ✅ Done | `title`, `body`, `icon`, `tag`, `close()`, `NotificationOptions`, `NotificationAction`, `requestPermission()` |
+| `Geolocation` | ✅ Done | `getCurrentPosition`, `watchPosition`, `clearWatch`, `GeolocationPosition`, `GeolocationCoordinates`, `PositionOptions` |
+| `Permissions` | ✅ Done | `query()`, `PermissionStatus`, `PermissionState`, `PermissionName`, `PermissionDescriptor` (+ Push, Midi, Device variants) |
 | `FullScreen API` | ❌ TODO | `requestFullscreen()`, `exitFullscreen()` |
 
 ---