feat(doc): update state of tests and touch app/jai module (#183)

## Description
<!-- Please add PR description (don't leave blank) - example: This PR
[adds/removes/fixes/replaces] the [feature/bug/etc] -->

This pull request improves the documentation and coverage of the testing
strategy for `jargons.dev`, reflecting the completion of business logic
test implementation and the integration of more robust API mocking. The
updates provide a clear overview of current test coverage, detail the
organization of test files, and outline next steps for future testing
phases.

### Key  Changes

* Updated the reported test coverage to **161 tests across 7 suites**
with a **99.4% success rate**, and clarified coverage for business logic
functions in `tests/README.md`.
* Added detailed breakdowns of business logic test coverage, including
number of test cases and areas covered for `submit-word`, `word-editor`,
`branch`, and `fork` functions.
* Marked Phase 2 (business logic tests) as complete, and described MSW
(Mock Service Worker) integration for realistic API testing.
* Expanded the test directory structure to include fixtures for test
data and GitHub API responses, as well as MSW handlers for API endpoint
mocking.
[[1]](diffhunk://#diff-dacac2ebf9792f0d23c0f922a744486ded01901957d5281290925acd89cf83acL34-R51)
[[2]](diffhunk://#diff-dacac2ebf9792f0d23c0f922a744486ded01901957d5281290925acd89cf83acR241-R258)
* Updated setup instructions to highlight MSW usage and provided
commands for running specific business logic tests.
* Added recommendations for using MSW for API testing and emphasized
testing error scenarios. Updated the roadmap to reflect the completion
of business logic tests and outlined plans for component, enhanced API,
and performance testing.
[[1]](diffhunk://#diff-dacac2ebf9792f0d23c0f922a744486ded01901957d5281290925acd89cf83acR215-R223)
[[2]](diffhunk://#diff-dacac2ebf9792f0d23c0f922a744486ded01901957d5281290925acd89cf83acR241-R258)

### Other Changes

* Clarified the location of the jAI module in the main `README.md` for
easier navigation.
* Updated `PULL_REQUEST_TEMPLATE` to use semantic heading.

## Related Issue
<!-- Please prefix the issue number with Fixes/Resolves - example: Fixes
#123 or Resolves #123 -->

Follow-up to

- #180 
- #181

## Screenshots/Screencasts
<!-- Please provide screenshots or video recording that demos your
changes (especially if it's a visual change) -->

NA

## Notes to Reviewer
<!-- Please state here if you added a new npm packages, or any extra
information that can help reviewer better review you changes -->

NA

Author: babblebey

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,18 +1,18 @@
-### Description
+## Description
 <!-- Please add PR description (don't leave blank) - example: This PR [adds/removes/fixes/replaces] the [feature/bug/etc] -->
 
 
 
-### Related Issue
+## Related Issue
 <!-- Please prefix the issue number with Fixes/Resolves - example: Fixes #123 or Resolves #123 -->
 
 
 
-### Screenshots/Screencasts
+## Screenshots/Screencasts
 <!-- Please provide screenshots or video recording that demos your changes (especially if it's a visual change) -->
 
 
 
-### Notes to Reviewer
+## Notes to Reviewer
 <!-- Please state here if you added a new npm packages, or any extra information that can help reviewer better review you changes -->
 

README.md

@@ -70,7 +70,7 @@ To get set-up follow these steps:
 
 ## AI Features - Powering ✨jAI
 
-<tt>jargons.dev</tt> includes **✨jAI** (jargons.dev AI) - an intelligent assistant that helps users explore and understand software engineering terms through AI-powered interactions.
+<tt>jargons.dev</tt> includes **✨jAI** (jargons.dev AI) - an intelligent assistant that helps users explore and understand software engineering terms through AI-powered interactions. Learn more in the **[apps/jai](./apps/jai/README.md)** module.
 
 ### Setup ✨jAI
 

tests/README.md

@@ -13,10 +13,12 @@ Comprehensive testing strategy for jargons.dev ensuring code quality and reliabi
 
 ## Current Test Coverage
 
-- **76 tests** across 3 test suites
+- **161 tests** across 7 test suites
+- **99.4% overall test success rate** (160 passing, 1 unrelated failure)
 - **98.5%** coverage on constants validation (`constants.js`)
 - **95.34%** coverage on crypto functions (`src/lib/utils/crypto.js`)
 - **100%** coverage on utility functions (`src/lib/utils/index.js`)
+- **Complete coverage** on business logic functions (`submit-word.js`, `word-editor.js`, `branch.js`, `fork.js`)
 
 ## Available Commands
 
@@ -31,10 +33,22 @@ npm run test:coverage # Generate detailed coverage report
 
 ```
 tests/
-├── setup.js                     # Test environment configuration
+├── setup.js                     # Test environment configuration with MSW
+├── fixtures/                    # Test data and API response mocks
+│   ├── test-data/
+│   │   └── index.js             # Sample words and repository details
+│   └── github-responses/
+│       └── index.js             # GitHub API response fixtures
+├── mocks/
+│   └── github-api.js            # MSW handlers for GitHub API endpoints
 └── unit/
     ├── constants/
     │   └── constants.test.js     # Project constants validation
+    ├── lib/                      # Business logic tests
+    │   ├── submit-word.test.js   # PR creation and submission logic
+    │   ├── word-editor.test.js   # Word file management operations
+    │   ├── branch.test.js        # Git branch operations
+    │   └── fork.test.js          # Repository forking logic
     └── utils/
         ├── crypto.test.js        # Encryption/decryption functions
         └── index.test.js         # Utility functions
@@ -48,11 +62,12 @@ tests/
 - **Crypto Functions** - Encryption/decryption with security validation and error handling
 - **Constants Validation** - Project configuration, labels, and SEO compliance
 
-### 🔄 Phase 2: Business Logic Tests (Planned)
+### ✅ Phase 2: Business Logic Tests (Complete)
 
-- Word management functions (`submit-word.js`, `word-editor.js`)
-- Git operations (`branch.js`, `fork.js`)
-- GitHub API interactions and error handling
+- **Word management functions** (`submit-word.js`, `word-editor.js`)
+- **Git operations** (`branch.js`, `fork.js`)
+- **GitHub API interactions** and error handling
+- **MSW (Mock Service Worker)** integration for realistic API testing
 
 ### 📋 Phases 3-5: Upcoming
 
@@ -82,6 +97,32 @@ tests/
 - **98.5% coverage** with configuration validation
 - Tests: PROJECT_REPO_DETAILS validation, LABELS consistency, SEO compliance
 
+### Phase 2 Implementation
+
+#### Submit Word Functions (`tests/unit/lib/submit-word.test.js`)
+
+- **19 test cases** covering PR creation and submission workflow
+- **100% coverage** of pull request title generation, template rendering, and label assignment
+- Tests: PR title formatting, template substitution, repository parsing, GitHub API error handling
+
+#### Word Editor Functions (`tests/unit/lib/word-editor.test.js`)
+
+- **26 test cases** covering word file management operations
+- **100% coverage** of word creation, updates, and retrieval
+- Tests: base64 encoding, template processing, path normalization, special character handling
+
+#### Branch Operations (`tests/unit/lib/branch.test.js`)
+
+- **24 test cases** covering Git branch management
+- **100% coverage** of branch creation, retrieval, and deletion
+- Tests: branch reference formatting, repository parsing, complex ref handling, error propagation
+
+#### Fork Operations (`tests/unit/lib/fork.test.js`)
+
+- **16 test cases** covering repository forking logic
+- **100% coverage** of fork detection, creation, and synchronization
+- Tests: GraphQL queries, fork status checking, automatic updates, nested error handling
+
 ## Writing Tests
 
 ### Test File Naming Convention
@@ -115,13 +156,21 @@ The test environment is configured in `tests/setup.js` with:
 - Environment variable mocking for crypto keys
 - GitHub configuration mocking
 - DOM testing utilities setup
+- **MSW (Mock Service Worker)** for GitHub API mocking
+- Comprehensive test fixtures for GitHub API responses
 
 ## Running Specific Tests
 
 ```sh
 # Run specific test file
 npm test -- tests/unit/utils/index.test.js
 
+# Run business logic tests
+npm test -- tests/unit/lib/
+
+# Run specific business logic function tests
+npm test -- tests/unit/lib/submit-word.test.js
+
 # Run tests matching pattern
 npm test -- --grep "crypto"
 
@@ -163,13 +212,15 @@ Coverage reports include:
 - **Keep tests isolated** - Each test should be independent
 - **Use meaningful assertions** - Prefer specific expectations over generic ones
 - **Mock external dependencies** - Isolate code under test from external systems
+- **Use MSW for API testing** - Mock GitHub API endpoints for realistic testing scenarios
+- **Test error scenarios** - Verify proper error handling and propagation chains
 
 ## GitHub Issues
 
 Track testing progress in our GitHub issues:
 
 - [#171: Phase 1 - Foundation Tests](https://github.com/babblebey/dictionry/issues/171) ✅
-- [#172: Phase 2 - Business Logic Tests](https://github.com/babblebey/dictionry/issues/172)
+- [#172: Phase 2 - Business Logic Tests](https://github.com/babblebey/dictionry/issues/172) ✅
 - [#173: Phase 3 - Component Tests](https://github.com/babblebey/dictionry/issues/173)
 - [#174: Phase 4 - Integration Tests](https://github.com/babblebey/dictionry/issues/174)
 - [#175: Phase 5 - E2E Tests](https://github.com/babblebey/dictionry/issues/175)
@@ -187,10 +238,21 @@ Track testing progress in our GitHub issues:
 - Environment variable mocking
 - Test utilities initialization
 - Global test configuration
+- **MSW server setup** for API mocking
+
+### `tests/fixtures/`
+
+- **Test data fixtures** - Sample words, repository details, and configuration
+- **GitHub API responses** - Realistic API response mocks for testing
+
+### `tests/mocks/`
+
+- **MSW handlers** - GitHub API endpoint mocking for comprehensive testing
 
 ## Next Steps
 
-1. **Phase 2 Implementation** - Begin business logic testing
-2. **API Mocking Setup** - Prepare for GitHub API interaction tests
-3. **Component Testing Framework** - Set up React/Astro component testing
+1. **Phase 3 Implementation** - Begin component testing for React/Astro components
+2. **Enhanced API Testing** - Expand MSW coverage for additional GitHub API endpoints
+3. **Component Testing Framework** - Set up React/Astro component testing infrastructure
 4. **CI/CD Integration** - Add automated testing to deployment pipeline
+5. **Performance Testing** - Add benchmarks for critical business logic functions