Initial commit of Descrybe v2 without local scratch artifacts.

Drop one-shot tmp/axe scripts and agent i18n scratch so the Gitea tree is deployable.

apps/api/internal/security/prompt.go

@@ -0,0 +1,99 @@
+package security
+
+import (
+	"regexp"
+	"strings"
+	"unicode"
+)
+
+const (
+	// MaxCampaignPromptRunes caps custom campaign / brand AI prompts (prompt-injection surface).
+	MaxCampaignPromptRunes = 8000
+	// MaxBrandFieldRunes caps individual brand kit text fields.
+	MaxBrandFieldRunes = 2000
+	// MaxBrandListItems caps dos/donts/preferred_terms entries.
+	MaxBrandListItems = 40
+	// MaxBrandListItemRunes caps each list entry.
+	MaxBrandListItemRunes = 200
+)
+
+var injectPhrase = regexp.MustCompile(`(?i)(ignore\s+previous|system\s*:|assistant\s*:|<\s*/?\s*script)`)
+
+// SanitizePrompt strips controls, soft-filters injection phrases, and truncates by runes.
+func SanitizePrompt(s string, maxRunes int) string {
+	if maxRunes <= 0 {
+		maxRunes = MaxCampaignPromptRunes
+	}
+	s = stripControls(strings.TrimSpace(s))
+	s = injectPhrase.ReplaceAllString(s, "[filtered]")
+	return TruncateRunes(s, maxRunes)
+}
+
+// CapPromptLength reports whether s exceeds max (rune count).
+func CapPromptLength(s string, maxRunes int) bool {
+	if maxRunes <= 0 {
+		maxRunes = MaxCampaignPromptRunes
+	}
+	n := 0
+	for range s {
+		n++
+		if n > maxRunes {
+			return true
+		}
+	}
+	return false
+}
+
+// SanitizeBrandList cleans and bounds a brand kit string list.
+func SanitizeBrandList(in []string) []string {
+	if len(in) == 0 {
+		return []string{}
+	}
+	out := make([]string, 0, len(in))
+	seen := map[string]struct{}{}
+	for _, s := range in {
+		s = SanitizePrompt(s, MaxBrandListItemRunes)
+		if s == "" {
+			continue
+		}
+		key := strings.ToLower(s)
+		if _, ok := seen[key]; ok {
+			continue
+		}
+		seen[key] = struct{}{}
+		out = append(out, s)
+		if len(out) >= MaxBrandListItems {
+			break
+		}
+	}
+	return out
+}
+
+func stripControls(s string) string {
+	if s == "" {
+		return ""
+	}
+	var b strings.Builder
+	b.Grow(len(s))
+	for _, r := range s {
+		if r == '\n' || r == '\t' || unicode.IsPrint(r) {
+			b.WriteRune(r)
+		}
+	}
+	return b.String()
+}
+
+// TruncateRunes truncates s to at most max runes.
+func TruncateRunes(s string, max int) string {
+	if max <= 0 {
+		return ""
+	}
+	n := 0
+	for i := range s {
+		if n == max {
+			return s[:i]
+		}
+		n++
+	}
+	return s
+}