chore(ci): add govulncheck, staticcheck, go vet, gofumpt gates

* Add lint/format checks to the Gitea release workflow and Makefile
  (targets: vet, fmt, fmt-check, staticcheck, govulncheck, check)
* Switch .golangci.json formatter from gofmt to gofumpt (extra.group-params)
* Bump golang.org/x/text 0.37.0 -> 0.39.0 for GO-2026-5970; re-vendor
* Fix staticcheck S1011 in pkg/diff; drop unused pgsql writer helpers
* Fix gocritic unnamedResult (pkg/diff) and rangeValCopy (pkg/pgsql)
* Apply gofumpt + goimports formatting across the tree

pkg/writers/template/formatters.go

@@ -57,7 +57,7 @@ func Indent(s string, spaces int) string {
 
 // IndentWith indents each line of a string with a custom prefix
 // Usage: {{ .Column.Description | indentWith "    " }}
-func IndentWith(s string, prefix string) string {
+func IndentWith(s, prefix string) string {
 	if s == "" {
 		return ""
 	}
@@ -93,7 +93,7 @@ func EscapeQuotes(s string) string {
 // Comment adds comment prefix to a string
 // Supports: "//" (Go, C++, etc.), "#" (Python, shell), "--" (SQL), "/* */" (block)
 // Usage: {{ .Table.Description | comment "//" }}
-func Comment(s string, style string) string {
+func Comment(s, style string) string {
 	if s == "" {
 		return ""
 	}