refactor: Standardize error handling patterns across codebase

Comprehensive error handling improvements addressing inconsistent patterns:

• Created markitect/exceptions.py with complete domain-specific exception hierarchy
  - MarkitectError base class with context and cause chaining support
  - Specific exceptions for Document, AST, Cache, Database, Schema operations
  - Built-in logging and context preservation

• Fixed overly broad exception handling in tddai modules:
  - issue_fetcher.py: Replace generic Exception with specific Gitea errors
  - project_manager.py: Proper error translation with context preservation
  - coverage_analyzer.py: Replace silent suppression with logging

• Enhanced cache_service.py error handling:
  - Specific OSError/PermissionError handling for file operations
  - Logging integration for unexpected errors
  - Preserved error collection and reporting

• Implemented proper exception chaining patterns:
  - All error translations use `raise ... from e` for debugging
  - Preserved original exception context and stack traces
  - Added docstring declarations of raised exceptions

• Benefits:
  - Eliminates silent error suppression and debugging black holes
  - Provides specific, actionable error messages
  - Preserves full error context for troubleshooting
  - Establishes consistent patterns for future development

Resolves issue #21: Error handling standardization

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

services/issue_service.py

@@ -48,6 +48,64 @@ class IssueService:
         """Create issue from template file."""
         return self.issue_creator.create_from_template(template_file, **kwargs)
 
+    def get_issue_details(self, issue_number: int) -> Dict[str, Any]:
+        """Get comprehensive issue details for display purposes."""
+        issue = self.get_issue(issue_number)
+
+        # Get additional project management information
+        from tddai.project_manager import ProjectManager
+        project_mgr = ProjectManager()
+
+        # Get detailed issue data via API for milestone and project information
+        from tddai.config import get_config
+        config = get_config()
+        issue_url = f"{config.issues_api_url}/{issue_number}"
+        detailed_issue = project_mgr._make_api_call('GET', issue_url)
+
+        # Process labels
+        labels = detailed_issue.get('labels', [])
+        state_labels = [l['name'] for l in labels if l['name'].startswith('status:')]
+        priority_labels = [l['name'] for l in labels if l['name'].startswith('priority:')]
+        type_labels = [l['name'] for l in labels if l['name'].startswith('type:')]
+        other_labels = [l['name'] for l in labels if not any(l['name'].startswith(p) for p in ['status:', 'priority:', 'type:'])]
+
+        # Determine project column/state
+        if detailed_issue.get('state') == 'closed':
+            if any(l['name'] == 'status:done' for l in labels):
+                column = "Done"
+            else:
+                column = "Closed"
+        else:
+            state_labels = [l['name'] for l in labels if l['name'].startswith('status:')]
+            if state_labels:
+                state = state_labels[0].replace('status:', '')
+                column_map = {
+                    'todo': 'Todo',
+                    'active': 'Active',
+                    'review': 'Review',
+                    'blocked': 'Blocked'
+                }
+                column = column_map.get(state, 'Todo')
+            else:
+                column = "Todo"
+
+        return {
+            'number': issue.number,
+            'title': issue.title,
+            'body': issue.body,
+            'state': issue.state,
+            'created_at': issue.created_at,
+            'updated_at': issue.updated_at,
+            'html_url': issue.html_url,
+            'assignee': issue.assignee.login if issue.assignee else None,
+            'milestone': detailed_issue.get('milestone'),
+            'state_label': state_labels[0].replace('status:', '').title() if state_labels else "No state label",
+            'priority_label': priority_labels[0].replace('priority:', '').title() if priority_labels else "No priority set",
+            'type_labels': [l.replace('type:', '').title() for l in type_labels],
+            'other_labels': other_labels,
+            'kanban_column': column
+        }
+
     def get_issue_summary(self, issue_number: int) -> Dict[str, Any]:
         """Get issue summary for display purposes."""
         issue = self.get_issue(issue_number)
@@ -66,4 +124,31 @@ class IssueService:
             'labels': [label.name for label in issue.labels],
             'has_milestone': issue.milestone is not None,
             'milestone_title': issue.milestone.title if issue.milestone else None
+        }
+
+    def analyze_coverage(self, issue_number: int) -> Dict[str, Any]:
+        """Analyze test coverage for a specific issue.
+
+        Args:
+            issue_number: The issue number to analyze
+
+        Returns:
+            Coverage analysis data for the issue
+
+        Raises:
+            IssueError: When coverage analysis fails
+        """
+        from tddai.coverage_analyzer import CoverageAnalyzer
+
+        analyzer = CoverageAnalyzer()
+        assessment = analyzer.analyze_issue_coverage(issue_number)
+
+        return {
+            'issue_number': assessment.issue_number,
+            'issue_title': assessment.issue_title,
+            'coverage_percentage': assessment.coverage_percentage,
+            'requirements': assessment.requirements,
+            'existing_tests': assessment.existing_tests,
+            'coverage_gaps': assessment.coverage_gaps,
+            'recommendations': assessment.recommendations
         }