refactor: enhance add-task fuzzy search and fix duplicate banner display

- **Remove hardcoded category system** in add-task that always matched 'Task management'
- **Eliminate arbitrary limits** in fuzzy search results (5→25 high relevance, 3→10 medium relevance, 8→20 detailed tasks)
- **Improve semantic weighting** in Fuse.js search (details=3, description=2, title=1.5) for better relevance
- **Fix duplicate banner issue** by removing console.clear() and redundant displayBanner() calls from UI functions
- **Enhance context generation** to rely on semantic similarity rather than rigid pattern matching
- **Preserve terminal history** to address GitHub issue #553 about eating terminal lines
- **Remove displayBanner() calls** from: displayHelp, displayNextTask, displayTaskById, displayComplexityReport, set-task-status, clear-subtasks, dependency-manager functions

The add-task system now provides truly relevant task context based on semantic similarity rather than arbitrary categories and limits, while maintaining a cleaner terminal experience.

Changes span: add-task.js, ui.js, set-task-status.js, clear-subtasks.js, list-tasks.js, dependency-manager.js

Closes #553

.taskmaster/config.json

@@ -1,8 +1,8 @@
 {
   "models": {
     "main": {
-      "provider": "openrouter",
-      "modelId": "qwen/qwen3-235b-a22b:free",
+      "provider": "anthropic",
+      "modelId": "claude-sonnet-4-20250514",
       "maxTokens": 50000,
       "temperature": 0.2
     },