feat: Add Admin Groups Management Module

- Introduced a new module for managing user groups (`usrgrp`) in the administration interface.
- Implemented CRUD operations for user groups: list, create, rename, and delete.
- Added authorization checks to ensure only users with appropriate permissions can manage groups.
- Created corresponding frontend JavaScript and SCSS files for the new module.
- Updated documentation to reflect the new group management functionality and its authorization model.
- Added SQL stored procedures for group management operations.
- Established a new login script for database access, ensuring proper security practices.

Fuchs/js/intranet/modules/fis.usrgrp.scss

@@ -0,0 +1,58 @@
+.ugpfrm {
+    padding: 1.5rem 2rem;
+
+    .ugp_grid {
+        border: 1px solid #e2e2e2;
+        border-radius: 0.5rem;
+        background: #fff;
+        box-shadow: 0 1px 3px rgba(50, 50, 50, 0.1);
+        overflow: hidden;
+        max-width: 32rem;
+    }
+
+    .ugp_row {
+        display: grid;
+        grid-template-columns: 1fr;
+        align-items: center;
+        padding: 0.55rem 1rem;
+        border-bottom: 1px solid #eee;
+
+        &:last-child { border-bottom: none; }
+    }
+
+    .ugp_row_hd {
+        background: $fuchs_blau;
+        color: #fff;
+        font-weight: bold;
+        font-size: 0.85rem;
+        text-transform: uppercase;
+        letter-spacing: 0.02em;
+        padding: 0.5rem 1rem;
+    }
+
+    .ugp_row:not(.ugp_row_hd) {
+        cursor: pointer;
+        transition: background-color 0.12s ease-in-out;
+
+        &:hover { background-color: #f3f6fb; }
+
+        &.selected {
+            background-color: rgba($fuchs_akzent, 0.12);
+            box-shadow: inset 3px 0 0 $fuchs_akzent;
+        }
+    }
+
+    .ugp_col_name { font-weight: 600; color: #222; }
+
+    .ugp_empty {
+        padding: 1.5rem 1rem;
+        text-align: center;
+        color: #777;
+    }
+
+    .ugp_err {
+        padding: 1rem 2rem;
+        color: #b00020;
+        font-weight: bold;
+    }
+}