feat: Implement Study Interview Mode as default study creation method

Study Interview Mode is now the DEFAULT for all study creation requests.
This intelligent Q&A system guides users through optimization setup with:

- 7-phase interview flow: introspection → objectives → constraints → design_variables → validation → review → complete
- Material-aware validation with 12 materials and fuzzy name matching
- Anti-pattern detection for 12 common mistakes (mass-no-constraint, stress-over-yield, etc.)
- Auto extractor mapping E1-E24 based on goal keywords
- State persistence with JSON serialization and backup rotation
- StudyBlueprint generation with full validation

Triggers: "create a study", "new study", "optimize this", any study creation intent
Skip with: "skip interview", "quick setup", "manual config"

Components:
- StudyInterviewEngine: Main orchestrator
- QuestionEngine: Conditional logic evaluation
- EngineeringValidator: MaterialsDatabase + AntiPatternDetector
- InterviewPresenter: Markdown formatting for Claude
- StudyBlueprint: Validated configuration output
- InterviewState: Persistent state management

All 129 tests passing.

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

docs/protocols/operations/OP_01_CREATE_STUDY.md

@@ -136,7 +136,59 @@ See `studies/M1_Mirror/README.md` for a complete parent README example.
 
 ---
 
-## Detailed Steps
+## Interview Mode (DEFAULT)
+
+**Study creation now uses Interview Mode by default.** This provides guided study creation with intelligent validation.
+
+### Triggers (Any of These Start Interview Mode)
+
+- "create a study", "new study", "set up study"
+- "create a study for my bracket"
+- "optimize this model"
+- "I want to minimize mass"
+- Any study creation request without "skip interview" or "manual"
+
+### When to Skip Interview Mode (Manual)
+
+Use manual mode only when:
+- Power user who knows the exact configuration
+- Recreating a known study configuration
+- User explicitly says "skip interview", "quick setup", or "manual config"
+
+### Starting Interview Mode
+
+```python
+from optimization_engine.interview import StudyInterviewEngine
+
+engine = StudyInterviewEngine(study_path)
+
+# Run introspection first (if model available)
+introspection = {
+    "expressions": [...],  # From part introspection
+    "model_path": "...",
+    "sim_path": "..."
+}
+
+session = engine.start_interview(study_name, introspection=introspection)
+action = engine.get_first_question()
+
+# Present action.message to user
+# Process answers with: action = engine.process_answer(user_response)
+```
+
+### Interview Benefits
+
+- **Material-aware validation**: Checks stress limits against yield
+- **Anti-pattern detection**: Warns about mass minimization without constraints
+- **Auto extractor mapping**: Maps goals to correct extractors (E1-E10)
+- **State persistence**: Resume interrupted interviews
+- **Blueprint generation**: Creates validated configuration
+
+See `.claude/skills/modules/study-interview-mode.md` for full documentation.
+
+---
+
+## Detailed Steps (Manual Mode - Power Users Only)
 
 ### Step 1: Gather Requirements