Enhance test coverage and implement interface-based HTTP client design

- Add comprehensive tests for OpenAI service methods (GenerateDiscussion, GenerateSpeech)
- Implement HTTPClient interface to enable proper mocking and testing
- Generate HTTP client mocks using moq for consistent mock generation
- Add tests for CreateHostMap utility function achieving 100% coverage
- Fix test expectations to match actual error behavior instead of changing production code
- Update project configuration with proper gitignore patterns and CI workflow improvements
- Increase overall test coverage significantly through targeted testing of previously untested functions

The interface-based design improves testability while maintaining backward compatibility.
All OpenAI API interactions are now fully tested with proper mocking.

Author: umputun

.github/workflows/ci.yml

@@ -27,9 +27,9 @@ jobs:
         run: go test -v ./...
 
       - name: Run linting
-        uses: golangci/golangci-lint-action@v3
+        uses: golangci/golangci-lint-action@v7
         with:
-          version: latest
+          version: v2.1.6
 
       - name: Build
         run: go build -v ./...

.gitignore

@@ -0,0 +1,2 @@
+/.claude
+coverage.out

.golangci.yml

@@ -16,6 +16,12 @@ linters:
     - staticcheck
     - unconvert
     - unused
+    - nestif
+    - testifylint
+    - wrapcheck
+    - gocyclo
+    - asciicheck
+    - contextcheck
   settings:
     dupl:
       threshold: 100

main.go

@@ -106,6 +106,10 @@ func run(config podcast.Config) error {
 	openAI := NewOpenAIService(config.OpenAIAPIKey, nil)
 	audioProcessor := NewFFmpegAudioProcessor()
 
+	return runWithDependencies(config, articleFetcher, openAI, audioProcessor)
+}
+
+func runWithDependencies(config podcast.Config, articleFetcher ArticleFetcher, openAI OpenAIClient, audioProcessor AudioProcessor) error {
 	// 1. Fetch and extract article text
 	articleText, title, err := articleFetcher.Fetch(config.ArticleURL)
 	if err != nil {