fix: typo `sql tempalte` and minor style issues in `internal/gen`

[pageton]

Summary

A few small issues in internal/gen/:

1. Typo in panic message

internal/gen/sqlparser.go:90:

panic(fmt.Sprintf("unsupported func %q in sql tempalte\n", f.Name))

tempalte → template

2. Abbreviated variable name pth

internal/gen/generator.go:110:

for pth, file := range g.Files {

pth is an abbreviation that saves 1 character over path. In a 30-line block it adds no value. Use path or filePath for readability.

3. Operator precedence ambiguity

internal/gen/generator.go:630:

if method.SQL.Where == "" && method.SQL.Select == "" || method.SQL.Raw != "" {

The || binds loosely. Add explicit parens to make intent clear:

if (method.SQL.Where == "" && method.SQL.Select == "") || method.SQL.Raw != "" {

4. Verbose local in sqlparser.go

internal/gen/sqlparser.go:326-343:

paramsCount := 0  // used in 4 adjacent lines
codes := []string{}  // used in 4 adjacent lines

Shorter names like count and lines would suffice for the narrow scope.