# Task: Complete rotation signals and macro view

## Goal
Implement the rotation signal generation and macro view endpoints for the sector rotation service.

## Requirements

### 1. Signal generation in `services/rotation_service.py`

Implement `generate_signals(ranked_sectors)` method:
- For each sector, determine rotation signal based on:
  - `rank_change > 0` → `"bullish"` (rising)
  - `rank_change < 0` → `"bearish"` (falling)  
  - `rank_change == 0` → `"neutral"` (unchanged)
- Return list of signal dicts with sector info and signal type
- Filter out sectors with insufficient data

### 2. Macro view in `routers/rotation.py`

Add `GET /api/v1/rotation/macro` endpoint:
- Returns top 3 rising sectors and bottom 3 falling sectors
- Includes sector name, ticker, momentum, and signal
- Response model: `MacroRotationResponse` with `rising` and `falling` lists

### 3. Add response model

Add `MacroRotationResponse` schema in `schemas/rotation.py`:
- `rising: list[RisingSector]`
- `falling: list[FallingSector]`
- Each sector: `sector_name`, `sector_ticker`, `momentum`, `signal`

## Acceptance Criteria
1. `generate_signals()` correctly classifies sectors
2. `/api/v1/rotation/macro` endpoint returns correct data
3. Response model is properly typed
4. Tests pass for new endpoints

## Files to Modify
- `src/backend/services/rotation_service.py`
- `src/backend/routers/rotation.py`
- `src/backend/schemas/rotation.py`

## Files to Read First
- `src/backend/services/rotation_service.py` — current state
- `src/backend/routers/rotation.py` — existing rotation endpoints
- `src/backend/schemas/rotation.py` — existing schemas