feat: Unified create command + consolidated enhancement flags

This commit includes two major improvements:

## 1. Unified Create Command (v3.0.0 feature)
- Auto-detects source type (web, GitHub, local, PDF, config)
- Three-tier argument organization (universal, source-specific, advanced)
- Routes to existing scrapers (100% backward compatible)
- Progressive disclosure: 15 universal flags in default help

**New files:**
- src/skill_seekers/cli/source_detector.py - Auto-detection logic
- src/skill_seekers/cli/arguments/create.py - Argument definitions
- src/skill_seekers/cli/create_command.py - Main orchestrator
- src/skill_seekers/cli/parsers/create_parser.py - Parser integration

**Tests:**
- tests/test_source_detector.py (35 tests)
- tests/test_create_arguments.py (30 tests)
- tests/test_create_integration_basic.py (10 tests)

## 2. Enhanced Flag Consolidation (Phase 1)
- Consolidated 3 flags (--enhance, --enhance-local, --enhance-level) → 1 flag
- --enhance-level 0-3 with auto-detection of API vs LOCAL mode
- Default: --enhance-level 2 (balanced enhancement)

**Modified files:**
- arguments/{common,create,scrape,github,analyze}.py - Added enhance_level
- {doc_scraper,github_scraper,config_extractor,main}.py - Updated logic
- create_command.py - Uses consolidated flag

**Auto-detection:**
- If ANTHROPIC_API_KEY set → API mode
- Else → LOCAL mode (Claude Code)

## 3. PresetManager Bug Fix
- Fixed module naming conflict (presets.py vs presets/ directory)
- Moved presets.py → presets/manager.py
- Updated __init__.py exports

**Test Results:**
- All 160+ tests passing
- Zero regressions
- 100% backward compatible

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

pyproject.toml

@@ -177,6 +177,7 @@ Documentation = "https://skillseekersweb.com/"
 skill-seekers = "skill_seekers.cli.main:main"
 
 # Individual tool entry points
+skill-seekers-create = "skill_seekers.cli.create_command:main"  # NEW: Unified create command
 skill-seekers-config = "skill_seekers.cli.config_command:main"
 skill-seekers-resume = "skill_seekers.cli.resume_command:main"
 skill-seekers-scrape = "skill_seekers.cli.doc_scraper:main"