refactor(workflow): remove all .active marker file references and sync documentation

Core Changes (10 files):
- commands: cli/execute.md, memory/docs.md, workflow/review.md, workflow/brainstorm/*.md
- agents: cli-execution-agent.md
- workflows: task-core.md, workflow-architecture.md

Transformations:
- Removed all .active-* marker file operations (touch/rm/find)
- Updated session discovery to directory-based (.workflow/sessions/)
- Updated directory structure examples to show sessions/ subdirectory
- Replaced marker-based state with location-based state

Reference Documentation (57 files):
- Auto-synced via analyze_commands.py script
- Includes all core file changes
- Updated command indexes (all-commands.json, by-category.json, etc.)

Migration complete: 100% .active marker references removed
Session state now determined by directory location only

.claude/commands/workflow/brainstorm/system-architect.md

@@ -186,8 +186,8 @@ IF update_mode = "incremental":
 ### ⚠️ Session Management - FIRST STEP
 Session detection and selection:
 ```bash
-# Check for active sessions
-active_sessions=$(find .workflow -name ".active-*" 2>/dev/null)
+# Check for existing sessions
+existing_sessions=$(find .workflow/sessions/ -name "WFS-*" -type d 2>/dev/null)
 if [ multiple_sessions ]; then
   prompt_user_to_select_session()
 else