Clean up codebase and fix server host binding for IPv6 support

Cleanup:
- Remove unused aircraft-icon.svg (replaced by type-specific icons)
- Remove test files: beast-dump-with-heli.bin, beast.test, main, old.json, ux.png
- Remove duplicate config.json.example (kept config.example.json)
- Remove empty internal/coverage/ directory
- Move CLAUDE.md to project root
- Update assets.go documentation to reflect current icon structure
- Format all Go code with gofmt

Server Host Binding Fix:
- Fix critical bug where server host configuration was ignored
- Add host parameter to Server struct and NewWebServer constructor
- Rename NewServer to NewWebServer for better clarity
- Fix IPv6 address formatting in server binding (wrap in brackets)
- Update startup message to show correct bind address format
- Support localhost-only, IPv4, IPv6, and interface-specific binding

This resolves the "too many colons in address" error for IPv6 hosts like ::1
and enables proper localhost-only deployment as configured.

Closes #15

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

assets/assets.go

@@ -6,7 +6,7 @@
 //   - index.html: Main web interface with aircraft tracking map
 //   - css/style.css: Styling for the web interface
 //   - js/app.js: JavaScript client for WebSocket communication and map rendering
-//   - aircraft-icon.svg: SVG icon for aircraft markers
+//   - icons/*.svg: Type-specific SVG icons for aircraft markers
 //   - favicon.ico: Browser icon
 //
 // The embedded filesystem is used by the HTTP server to serve static content
@@ -16,11 +16,11 @@ package assets
 import "embed"
 
 // Static contains all embedded static web assets from the static/ directory.
-// 
+//
 // Files are embedded at build time and can be accessed using the standard
 // fs.FS interface. Path names within the embedded filesystem preserve the
 // directory structure, so files are accessed as:
-//   - "static/index.html" 
+//   - "static/index.html"
 //   - "static/css/style.css"
 //   - "static/js/app.js"
 //   - etc.