Instagram Collector

# Instagram Collector Skill

## Purpose
Collects Instagram profile data for a given handle using the Apify Instagram Profile Scraper. Extracts follower count, engagement metrics, posting frequency, and top hashtags. This collector feeds into the Marketing Audit Pipeline to populate the Instagram Performance section of the final report.

## Input Schema
```typescript
// Function signature
collectInstagram(handle: string): Promise<InstagramData>

// The handle parameter is the Instagram username without the @ symbol.
// Example: "gymshark" (not "@gymshark")
```

## Output Schema
```typescript
interface InstagramData {
 followers: number;
 posts: number;
 engagementRate: number; // Calculated: (avgLikes + avgComments) / followers * 100
 postingFrequency: string; // e.g. "1.2 posts/day", "3 posts/week", "unknown"
 avgLikes: number;
 avgComments: number;
 topHashtags: string[]; // Up to 10 most-used hashtags from recent posts
 error?: string; // Present only when collector fails
}
```

## API Dependencies
- **API Name:** Apify Instagram Profile Scraper
- **Actor ID:** `apify~instagram-profile-scraper`
- **Endpoint:** `https://api.apify.com/v2/acts/apify~instagram-profile-scraper/runs`
- **Auth:** `APIFY_API_TOKEN` environment variable
- **Cost estimate:** ~$0.005 per run on Apify free/paid tier
- **Rate limits:** Depends on Apify plan; free tier allows limited concurrent runs

## Implementation Pattern

### Data Flow
1. Receive `handle` string from the pipeline
2. Call `apifyService.scrapeInstagramProfile(handle)` which starts an Apify actor run
3. Apify runs asynchronously -- the service polls for completion (timeout: 60s)
4. Fetch the actor's dataset results once complete
5. Map the raw Apify response to the `InstagramData` interface

### Engagement Rate Calculation
```typescript
engagementRate = ((avgLikes + avgComments) / followers) * 100;
```
- If `followers` is 0, set `engagementRate` to 0 to avoid division by zero
- Engagement rate is expressed as a percentage (e....