Add EXIF/metadata extraction provider (#9)

[C0MPL3XDEV]

Summary

• New provider for extracting metadata from images (EXIF: GPS, device, software, camera settings) and PDF documents (author, title, creator, producer)
• MetadataResult model with typed fields for both file types
• GPS DMS-to-decimal conversion for geolocation data
• CLI command with --output, --show-pii, --save-to flags

Files changed

• eagleosint/providers/metadata.py — new provider with image and PDF extraction
• eagleosint/models.py — MetadataResult model
• eagleosint/cli.py — metadata command + menu entry
• tests/test_metadata.py — 16 tests covering DMS conversion, image/PDF extraction, provider logic
• pyproject.toml — added Pillow, pdfplumber, piexif, reportlab

Test plan

• 174 tests pass
• Image metadata extraction (dimensions, EXIF with GPS/device/software)
• PDF metadata extraction (author, title, pages, producer)
• GPS DMS-to-decimal conversion (N/S/E/W, tuples, edge cases)
• Unsupported file types and missing files handled gracefully