docs(ui-design): eliminate output-then-save ambiguity in workflow documentation

Clarified file writing patterns across UI design workflows to prevent confusion
between "generate content as output then save" vs "direct write to file" approaches.

Changes:
- extract.md: Merged Phase 2 & 3 to unify style synthesis and file write operations
  * Updated phase title to emphasize direct file writing
  * Added explicit note about internal processing without context output
  * Consolidated parse-and-write step into single atomic operation

- imitate-auto.md: Added clarifying comments for orchestrator file transformation
  * Documented that Phase 2 uses orchestrator-level read-process-write pattern
  * Explained this as performance optimization to bypass consolidate phase

The entire UI design workflow now consistently follows clear file operation patterns
with no ambiguous intermediate output steps.

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

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

.claude/commands/workflow/ui-design/imitate-auto.md

@@ -267,6 +267,8 @@ SlashCommand(command)  # → Phase 2
 ```bash
 REPORT: "🚀 Phase 2: Fast token adaptation (bypassing consolidate)"
 
+# Note: Orchestrator directly reads and transforms files here (not delegating to agent)
+# This is a performance optimization to bypass the full consolidate phase
 style_cards = Read({base_path}/style-extraction/style-cards.json)
 style_card = style_cards.style_cards[0]
 
@@ -274,7 +276,7 @@ design_tokens = style_card.proposed_tokens
 philosophy = style_card.design_philosophy
 style_name = style_card.name
 
-# Write design-tokens.json directly
+# Write design-tokens.json directly (orchestrator-level file transformation)
 Write({base_path}/style-consolidation/style-1/design-tokens.json, JSON.stringify(design_tokens, null, 2))
 
 # Create minimal style-guide.md