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>

internal/client/beast.go

@@ -39,15 +39,15 @@ import (
 // continuously processes incoming messages until stopped or the source
 // becomes unavailable.
 type BeastClient struct {
-	source   *merger.Source    // Source configuration and status
-	merger   *merger.Merger    // Data merger for multi-source fusion
-	decoder  *modes.Decoder    // Mode S/ADS-B message decoder
-	conn     net.Conn          // TCP connection to Beast source
-	parser   *beast.Parser     // Beast format message parser
+	source   *merger.Source      // Source configuration and status
+	merger   *merger.Merger      // Data merger for multi-source fusion
+	decoder  *modes.Decoder      // Mode S/ADS-B message decoder
+	conn     net.Conn            // TCP connection to Beast source
+	parser   *beast.Parser       // Beast format message parser
 	msgChan  chan *beast.Message // Buffered channel for parsed messages
-	errChan  chan error        // Error reporting channel
-	stopChan chan struct{}     // Shutdown signal channel
-	wg       sync.WaitGroup    // Wait group for goroutine coordination
+	errChan  chan error          // Error reporting channel
+	stopChan chan struct{}       // Shutdown signal channel
+	wg       sync.WaitGroup      // Wait group for goroutine coordination
 
 	// Reconnection parameters
 	reconnectDelay time.Duration // Initial reconnect delay
@@ -102,9 +102,9 @@ func (c *BeastClient) Start(ctx context.Context) {
 // Stop gracefully shuts down the client and all associated goroutines.
 //
 // The shutdown process:
-//   1. Signals all goroutines to stop via stopChan
-//   2. Closes the TCP connection if active
-//   3. Waits for all goroutines to complete
+//  1. Signals all goroutines to stop via stopChan
+//  2. Closes the TCP connection if active
+//  3. Waits for all goroutines to complete
 //
 // This method blocks until the shutdown is complete.
 func (c *BeastClient) Stop() {
@@ -118,11 +118,11 @@ func (c *BeastClient) Stop() {
 // run implements the main client connection and reconnection loop.
 //
 // This method handles the complete client lifecycle:
-//   1. Connection establishment with timeout
-//   2. Exponential backoff on connection failures
-//   3. Message parsing and processing goroutine management
-//   4. Connection monitoring and failure detection
-//   5. Automatic reconnection on disconnection
+//  1. Connection establishment with timeout
+//  2. Exponential backoff on connection failures
+//  3. Message parsing and processing goroutine management
+//  4. Connection monitoring and failure detection
+//  5. Automatic reconnection on disconnection
 //
 // The exponential backoff starts at reconnectDelay (5s) and doubles on each
 // failure up to maxReconnect (60s), then resets on successful connection.
@@ -210,10 +210,10 @@ func (c *BeastClient) readMessages() {
 // processMessages runs in a dedicated goroutine to decode and merge aircraft data.
 //
 // For each received Beast message, this method:
-//   1. Decodes the Mode S/ADS-B message payload
-//   2. Extracts aircraft information (position, altitude, speed, etc.)
-//   3. Updates the data merger with new aircraft state
-//   4. Updates source statistics (message count)
+//  1. Decodes the Mode S/ADS-B message payload
+//  2. Extracts aircraft information (position, altitude, speed, etc.)
+//  3. Updates the data merger with new aircraft state
+//  4. Updates source statistics (message count)
 //
 // Invalid or unparseable messages are silently discarded to maintain
 // system stability. The merger handles data fusion from multiple sources
@@ -262,9 +262,9 @@ func (c *BeastClient) processMessages() {
 // All clients share the same data merger, enabling automatic data fusion
 // and conflict resolution across multiple receivers.
 type MultiSourceClient struct {
-	clients []*BeastClient    // Managed Beast clients
-	merger  *merger.Merger    // Shared data merger for all sources
-	mu      sync.RWMutex      // Protects clients slice
+	clients []*BeastClient // Managed Beast clients
+	merger  *merger.Merger // Shared data merger for all sources
+	mu      sync.RWMutex   // Protects clients slice
 }
 
 // NewMultiSourceClient creates a client manager for multiple Beast format sources.
@@ -292,9 +292,9 @@ func NewMultiSourceClient(merger *merger.Merger) *MultiSourceClient {
 // AddSource registers and configures a new Beast format data source.
 //
 // This method:
-//   1. Registers the source with the data merger
-//   2. Creates a new BeastClient for the source
-//   3. Adds the client to the managed clients list
+//  1. Registers the source with the data merger
+//  2. Creates a new BeastClient for the source
+//  3. Adds the client to the managed clients list
 //
 // The source is not automatically started; call Start() to begin connections.
 // Sources can be added before or after starting the multi-source client.