Add custom logger with source location tracking and remove verbose database logs

- Create internal/logger package with Logger wrapper around slog
- Logger automatically adds source file, line number, and function name to all log entries
- Use golang.org/x/term to properly detect if stdout is a terminal
- Replace all slog.Logger usage with logger.Logger throughout the codebase
- Remove verbose logging from database GetStats() method
- Update all constructors and dependencies to use the new logger

internal/database/slowquery.go

@@ -3,14 +3,15 @@ package database
 import (
 	"context"
 	"database/sql"
-	"log/slog"
 	"time"
+
+	"git.eeqj.de/sneak/routewatch/internal/logger"
 )
 
 const slowQueryThreshold = 50 * time.Millisecond
 
 // logSlowQuery logs queries that take longer than slowQueryThreshold
-func logSlowQuery(logger *slog.Logger, query string, start time.Time) {
+func logSlowQuery(logger *logger.Logger, query string, start time.Time) {
 	elapsed := time.Since(start)
 	if elapsed > slowQueryThreshold {
 		logger.Debug("Slow query", "query", query, "duration", elapsed)
@@ -47,7 +48,7 @@ func (d *Database) exec(query string, args ...interface{}) error {
 // loggingTx wraps sql.Tx to log slow queries
 type loggingTx struct {
 	*sql.Tx
-	logger *slog.Logger
+	logger *logger.Logger
 }
 
 // QueryRow wraps sql.Tx.QueryRow to log slow queries