Composable Strategies + Optimizer Best Params in Dashboard

[Muratich]

Depends on: #108, #112, Samy GridOptimizer, #121

Dashboard is a visualizer only — no strategy builder, no rule editor.

Backend (main.py):

• Load composable YAML strategies into the dashboard catalogue (Composable Strategy Foundation (YAML, compile, choices) #108)
• On bootstrap (or agreed CLI): run GridOptimizer per composable strategy
• Pick rank branch ruleset #1 param set (Optimizer Results Schema and Grid Ranking #121 schema)
• Run backtest with those params (or reuse grid metrics if already computed)
• Write results into data/runtime-dashboard.json — same shape as today

Frontend:

• No new pages or optimizer tables
• Existing cards: ranking, metrics, chart, trade_log
• Composable params: render choices from parameter_specs as dropdowns
  (not free-number input only)

Out of scope:

• YAML / rules / series editor
• Separate optimizer results screen (#123 — closed)
• POST /api/optimize-strategy as a standalone feature (use bootstrap/CLI)

Definition of Done:

• ma_rsi_composable appears in dashboard with optimizer-best params
• Top-N strategy ranking works (build_top_n, unchanged)
• Same metrics/charts/trade_log display as legacy strategies
• Manual smoke: bootstrap → cards show best params + ranking