add mapped drives card

Mapped drives existed only as a comma-joined line in the user context card, which is fine for three drives and unreadable for a dozen. They now get their own list card in Monitors: one row per letter, remote path as meta, health as a badge. Reuses the statecolor/levels vocabulary the tracked-services cards already declare rather than new CSS. Only unhealthy drives are coloured. Green on every working drive makes the broken one just another badge in a row of badges, and the card exists to make the exception findable at a glance. Unhealthy rows sort first for the same reason - a user with a dozen mappings should not hunt for the broken one - and the sort is on health alone, so drive-letter order survives within each group and the list does not reshuffle between refreshes. The merge logic is untouched. _mapped_drive_rows now returns structured rows and the user-context summary line is built from them, so the card and the line cannot drift apart about a drive's status. The two silent-failure paths are mutation-tested: forcing every badge green failed 7 tests, and the first sort test passed a mutation that added a secondary key because every broken drive in it said the same word - it now uses statuses that would reorder under a text sort. Also corrects a stale warning claiming the merge is untested; it has been covered since Phase 1.

plugins/endpoints/plugin.py

@@ -557,6 +557,39 @@ class EndpointsPlugin(BasePlugin):
                 'position': 15,
                 'group': 'monitors',
             },
+            {
+                # Session-scoped, so it sits with the other things watched
+                # rather than acted on. The user context card still carries a
+                # one-line summary; this is the same data with room to show a
+                # remote path and a per-drive badge, and both are built from
+                # _mapped_drive_rows so they cannot disagree.
+                #
+                # Room reserved here for the future one-click reconnect: the
+                # list render already supports a row action, so adding it is a
+                # map/commandendpoint change rather than a new card.
+                'id': 'endpoints-mappeddrives',
+                'title': 'Mapped drives',
+                'assettypes': ['computer'],
+                'endpoint': '/api/endpoints/asset/{assetid}/mappeddrives',
+                'render': 'list',
+                'collapsible': True,
+                'status': {
+                    'key': 'statecolor',
+                    'levels': {
+                        'green': 'ok',
+                        'yellow': 'warning',
+                        'red': 'critical',
+                    },
+                },
+                'map': {
+                    'title': 'drive',
+                    'meta': [{'key': 'remote', 'mono': True}],
+                    'badge': {'label': 'statuslabel', 'color': 'statecolor'},
+                },
+                'empty': 'No mapped drives reported.',
+                'position': 21,
+                'group': 'monitors',
+            },
             {
                 # Volumes and physical drive health in one card, as two
                 # sections. VISUAL GROUPING ONLY: the two tables share no key