refactor(workflow): eliminate ambiguous wait/completion terminology

Remove ambiguous "wait for completion" expressions that could be misinterpreted as waiting for an external command. Replace with clear execution-blocking language.

Changes:
- "WAIT for completion" → "Execute phase (blocks until finished)"
- "Upon each phase completion" → "When each phase finishes executing"
- "execution pauses until completion" → "execution pauses until the command finishes"

Affected files (6):
- brainstorm/auto-parallel.md: 3 changes
- plan.md: 3 changes
- tdd-plan.md: 1 change
- test-gen.md: 1 change
- ui-design/explore-auto.md: 12 changes
- ui-design/imitate-auto.md: 10 changes

Impact: Clarifies that SlashCommand is blocking execution, not waiting for separate completion task

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

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

.claude/commands/workflow/test-gen.md

@@ -33,7 +33,7 @@ allowed-tools: SlashCommand(*), TodoWrite(*), Read(*), Bash(*)
 3. **Parse Every Output**: Extract required data from each phase for next phase
 4. **Sequential Execution**: Each phase depends on previous phase's output
 5. **Complete All Phases**: Do not return to user until Phase 5 completes (summary returned)
-6. **Track Progress**: Update TodoWrite after every phase completion
+6. **Track Progress**: Update TodoWrite when each phase finishes executing
 7. **Automatic Detection**: context-gather auto-detects test session and gathers source session context
 8. **Parse --use-codex Flag**: Extract flag from arguments and pass to Phase 4 (test-task-generate)
 9. **Command Boundary**: This command ends at Phase 5 summary. Test execution is NOT part of this command.