feat: add id, groupId, and groupTitle support for Windows notifications

[bitdisaster]

Description of Change

This PR extends the Windows notification implementation to support the id, groupId, and groupTitle properties, bringing feature parity with macOS and adding Windows-specific header grouping support.

Changes

New Features:

• id property now works on Windows — maps directly to the toast notification’s Tag property for deduplication and removal.
• groupId property now works on Windows — it serves two purposes:
  • together with id it uniquely identifies a notification in memory
  • maps to the toast notification’s header id property for grouping in Action Center
• groupTitle property (Windows only) — when both groupId and groupTitle are specified, a <header> element is generated in the toast XML to display a visual group header.

Validation:

• Added length validation for id and groupId on Windows (max 64 UTF-16 characters) with descriptive error messages.

Internal Changes:

• Removed FastHash encoding of notification IDs — the raw id is now used directly as the Windows toast Tag.
• Added debug logging for group and tag values when ELECTRON_DEBUG_NOTIFICATIONS is set.

Tests:

• Extended existing macOS tests to also run on Windows (id, groupId properties).
• Added Windows-specific tests for groupTitle.
• Added validation tests for length limits.

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Example Usage

const { Notification } = require('electron')

// Basic usage with id and groupId
const n = new Notification({
  id: 'msg-123',
  groupId: 'chat-channel-1',
  title: 'New Message',
  body: 'Hello!'
})

// With header grouping (Windows only)
const n2 = new Notification({
  id: 'msg-456',
  groupId: 'camping-trip',
  groupTitle: 'Camping Trip 🏕️',
  title: 'New Message',
  body: 'Are you coming?'
})

Checklist

• PR description included
• I have built and tested this PR
• npm test passes
• tests are changed or added
• relevant API documentation, tutorials, and examples are updated and follow the documentation style guide
• PR release notes describe the change in a way relevant to app developers, and are capitalized, punctuated, and past tense.

Release Notes

Notes: