feat: ship phase 1 step 1 foundation

[tradersurfer]

Phase 1, Step 1 Implementation

Implements the five approved foundations for LEVI public alpha:

What's Included

• User Trading Profiles — Validated profiles with safe paper-trading defaults (1% per trade, 3% daily loss limit)
• Mode Router — Deterministic policies for day trading, swing trading, and investing/holding
• User Workspaces — Isolated, configurable per-user workspace with MEMORY.md, MOOD.md, BEHAVIOR.md
• Evidence Contract — Vendor-neutral evidence model supporting screenshots, CSV, Excel, PDF, charts, broker statements, options chains, and more
• What You Need Gate — Pre-analysis evidence validation that blocks only on missing required inputs
• FastAPI Integration — /api/what-you-need endpoint on existing application

Scope Integrity

✅ Zero scope drift
✅ No authentication
✅ No broker connections
✅ No market-data integrations
✅ No file parsers (protocol only)
✅ Existing paper-trading and alert modes unchanged

Testing

✅ 31 total tests passing (11 new focused tests)
✅ All security isolation tests pass (user/evidence boundaries enforced)
✅ Path traversal prevention verified
✅ Cross-user access prevention verified

Changes

• 21 files changed
• 791 insertions
• 4 deletions
• 1 commit: 165b0cb

Next Steps

After merge to main: Begin Phase 2 parallel workstreams

• Phase 2A: Evidence ingestion (parsers, storage)
• Phase 2B: Broker paper adapter
• Phase 3: Market data feeds

Ready for public v0.1.0 alpha (paper trading only).