Add relay count tracking workflow with dual charts

This commit adds:
- New GitHub workflow to track relay counts
- Two charts: BitChat-compatible relays and total functioning relays
- Extended history for both charts (70 days)
- Project structure improvements with scripts and assets directories
- Updated documentation in README.md and other files
- Dependencies in requirements.txt

PROJECT_STRUCTURE.md

@@ -0,0 +1,23 @@
+# Project Organization
+
+This project is organized as follows:
+
+## Core Files
+- `nostr_relay_discovery.py` - Python script for discovering functioning Nostr relays
+- `filter_bitchat_relays.sh` - Shell script to filter relays for BitChat capability
+- `relays_geo_lookup.sh` - Shell script to geolocate relay servers
+- `nostr_relays.csv` - The main output file with relay URLs and geolocation data
+
+## Directories
+- `/assets` - Contains generated images and other static resources
+  - `relay_count_chart.png` - Chart showing relay count history
+- `/scripts` - Utility scripts for analysis and visualization
+  - `track_relay_counts.py` - Script for analyzing relay count changes
+- `/.github/workflows` - GitHub Actions workflow definitions
+  - `update-relay-data.yml` - Workflow that updates relay data daily
+  - `relay-count-tracker.yml` - Workflow that tracks relay count changes
+
+## GitHub Workflows
+The project uses two automated workflows:
+1. `update-relay-data.yml` - Runs daily at 6:00 AM UTC to update the relay data
+2. `relay-count-tracker.yml` - Runs after the update workflow to track and visualize changes