fix!: rewrite spying implementation to make mocking more intuitive

[sheremet-va]

Description

Fixes #8319
Fixes #8307
Fixes #6948
Fixes #8331
Fixes #8134
Fixes #8345

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commit: 4f48ca9

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[Copilot]

Pull Request Overview

This PR implements a significant rewrite of the spying/mocking implementation to make module mocking more logical and address multiple long-standing issues. The changes focus on creating a custom mock implementation to replace the reliance on tinyspy, improving consistency between different execution environments, and providing better module mocking behavior.

Key changes include:

• Complete rewrite of the spy implementation with a custom mock system
• Improved module mocking behavior with better instance/prototype state management
• Enhanced constructor support and class mocking capabilities

Reviewed Changes

Copilot reviewed 30 out of 31 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
packages/spy/src/index.ts	Complete rewrite implementing custom mock system replacing tinyspy
packages/spy/src/types.ts	New type definitions for the mock system
packages/spy/package.json	Removed tinyspy dependency
packages/mocker/src/automocker.ts	Updated to use new createMockInstance API
packages/vitest/src/integrations/vi.ts	Updated to use new mock clearing/resetting functions
test/core/test/spy.test.ts	Added test for ignoring nodejs promisify symbol
docs/guide/module-mocking.md	New comprehensive module mocking guide

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported