Improve grep search (#30843) (#30850)

Backport #30843 by wxiaoguang

Reduce the context line number to 1, make "git grep" search respect the
include/exclude patter, and fix #30785

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/setting/glob.go

@@ -0,0 +1,32 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package setting
+
+import "github.com/gobwas/glob"
+
+type GlobMatcher struct {
+	compiledGlob  glob.Glob
+	patternString string
+}
+
+var _ glob.Glob = (*GlobMatcher)(nil)
+
+func (g *GlobMatcher) Match(s string) bool {
+	return g.compiledGlob.Match(s)
+}
+
+func (g *GlobMatcher) PatternString() string {
+	return g.patternString
+}
+
+func GlobMatcherCompile(pattern string, separators ...rune) (*GlobMatcher, error) {
+	g, err := glob.Compile(pattern, separators...)
+	if err != nil {
+		return nil, err
+	}
+	return &GlobMatcher{
+		compiledGlob:  g,
+		patternString: pattern,
+	}, nil
+}