docs(ai-docs): add patterns documentation - TypeScript, React, MobX, Web Components, Testing

[ciscoRankush]

COMPLETES N/A - Documentation Enhancement

This pull request addresses

Adding comprehensive pattern documentation to guide AI assistants and developers on the coding standards and patterns used in the Contact Center Widgets codebase.

by making the following changes

• Added ai-docs/patterns/typescript-patterns.md - TypeScript conventions, type definitions, and best practices
• Added ai-docs/patterns/react-patterns.md - React component patterns, hooks, and lifecycle management
• Added ai-docs/patterns/mobx-patterns.md - MobX state management patterns with observer HOC
• Added ai-docs/patterns/web-component-patterns.md - r2wc patterns for Web Component wrappers
• Added ai-docs/patterns/testing-patterns.md - Jest and Playwright testing patterns

Change Type

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Tooling change
• Internal code refactor

The following scenarios were tested

• The testing is done with the amplify link

The GAI Coding Policy And Copyright Annotation Best Practices

• GAI was not used (or, no additional notation is required)
• Code was generated entirely by GAI
• GAI was used to create a draft that was subsequently customized or modified
• Coder created a draft manually that was non-substantively modified by GAI (e.g., refactoring was performed by GAI on manually written code)
• Tool used for AI assistance (GitHub Copilot / Other - specify)
  • Github Copilot
  • Other - Please Specify: Cursor AI
• This PR is related to
  • Feature
  • Defect fix
  • Tech Debt
  • Automation

Checklist before merging

• I have not skipped any automated checks
• All existing and new tests passed
• I have updated the testing document
• I have tested the functionality with amplify link

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