fix: Remove log.Fatal in favor of returning errors (#953)

* fix: Remove log.Fatal in favor of returning errors

This change is useful for including error tracking, which needs the
application to not terminate immediately, and instead give the tracer
time to capture and flush errors.

* Fix CodeRabbit issues

---------

Co-authored-by: Matthew Kilgore <matthew@kilgore.dev>

backend/internal/data/migrations/migrations.go

@@ -3,6 +3,8 @@ package migrations
 
 import (
 	"embed"
+	"fmt"
+
 	"github.com/rs/zerolog/log"
 )
 
@@ -17,15 +19,16 @@ var sqliteFiles embed.FS
 // migration files in the binary at build time. The function takes a string
 // parameter "dialect" which specifies the SQL dialect to use. It returns an
 // embedded file system containing the migration files for the specified dialect.
-func Migrations(dialect string) embed.FS {
+func Migrations(dialect string) (embed.FS, error) {
 	switch dialect {
 	case "postgres":
-		return postgresFiles
+		return postgresFiles, nil
 	case "sqlite3":
-		return sqliteFiles
+		return sqliteFiles, nil
 	default:
-		log.Fatal().Str("dialect", dialect).Msg("unknown sql dialect")
+		log.Error().Str("dialect", dialect).Msg("unknown sql dialect")
+		return embed.FS{}, fmt.Errorf("unknown sql dialect: %s", dialect)
 	}
 	// This should never get hit, but just in case
-	return sqliteFiles
+	return sqliteFiles, nil
 }