fix: security audit — patch vulnerabilities V-02 through V-16

- V-02: XSS via innerHTML in profile.js — wrap err.message in escapeHtml()
- V-03: IDOR upload to other users' folders — add folder ownership check
- V-04: IDOR create folders in other users' trees — add parent ownership check
- V-06: Content-Disposition header injection — RFC 5987 percent-encoding
- V-08: WebDAV MOVE/COPY destination without ownership — add assert_owner checks
- V-09: .gitignore missing cert/key patterns — add *.pem, *.key, *.p12, etc.
- V-11: Username accepts XSS payloads — restrict to [a-zA-Z0-9._-]
- V-12: Minimal email validation — reject forbidden chars, require domain dot
- V-13: admin_reset_password doesn't invalidate sessions — revoke all sessions
- V-14: Rate limiting bypassable via X-Forwarded-For — gate behind OXICLOUD_TRUST_PROXY_HEADERS
- V-15: Cookie Secure flag off by default — default to true (safe-by-default)
- V-16: LIKE wildcard injection in searches — add like_escape() helper across 9 sites

src/infrastructure/repositories/pg/folder_db_repository.rs

@@ -739,7 +739,7 @@ impl FolderRepository for FolderDbRepository {
                 } else {
                     " AND fo.name ILIKE $3"
                 },
-                Some(format!("%{}%", name)),
+                Some(super::like_escape(name)),
             ),
             _ => ("", None),
         };
@@ -861,7 +861,7 @@ impl FolderRepository for FolderDbRepository {
         user_id: &str,
     ) -> Result<Vec<Folder>, DomainError> {
         let (where_extra, name_pattern) = match name_contains {
-            Some(name) if name.len() >= 3 => (" AND fo.name ILIKE $3", Some(format!("%{}%", name))),
+            Some(name) if name.len() >= 3 => (" AND fo.name ILIKE $3", Some(super::like_escape(name))),
             _ => ("", None),
         };
 
@@ -908,7 +908,7 @@ impl FolderRepository for FolderDbRepository {
         query: &str,
         limit: usize,
     ) -> Result<Vec<Folder>, DomainError> {
-        let pattern = format!("%{}%", query);
+        let pattern = super::like_escape(query);
         let limit_i64 = limit as i64;
 
         let rows: Vec<FolderRow> = if let Some(pid) = parent_id {