Add photo management for models and employees; fix stale detail navigation

Model photos: upload/replace/delete on /api/models/<id>/image (admin),
stored under instance/modelimages/ with a public serve route; thumbnail
plus Upload/Replace/Remove controls in the Models settings modal; the
URL field remains as a manual alternative.

Employee photos, mode-aware: self-hosted directory employees get
upload/replace/delete (photo-<sso> under instance/employeephotos/,
employees plugin migration 0002); external directory mode passes the
HR-supplied picture URL through read-only (writes 409). One resolver
feeds both consumers - the shopfloor recognition/recert kiosk cards and
the employee detail hero - in either mode.

Navigation fix: router-view is keyed on route path, so following a
relationship link between two assets of the same type (machine ->
dualpath machine) reloads the page instead of showing stale content;
query-only URL changes still avoid a remount.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/IMPORT-API.md

@@ -194,10 +194,16 @@ Per-plugin extension fields:
 | `vendors` | `POST /api/vendors` | `vendor` -> `vendor` | `vendor` |
 | `machinetypes` | `POST /api/modeltypes` | `machinetype` -> `modeltype`; set `category` (Equipment/Computer/...) | `modeltype` |
 | `models` | `POST /api/models` | `modelnumber`, `vendorid` (remapped), `machinetypeid` -> `modeltypeid`, `notes`, `image` -> `imageurl`, `documentationpath` -> `documentationurl` | `modelnumber` + `vendor` |
+
+`imageurl` imports as a plain URL string (an external URL or a legacy
+`/images/models/*` path). Binary photos are not part of the import payload;
+upload them after import via `POST /api/models/<modelid>/image` (multipart
+`file`), which stores the file under `instance/modelimages/` and rewrites
+`imageurl` to the served URL.
 | `businessunits` | `POST /api/businessunits` | `businessunit` -> `businessunit` | `businessunit` |
 | `operatingsystems` | `POST /api/operatingsystems` | `operatingsystem` -> `osname` | `osname` (+`osversion`) |
 | `machinestatus` | `POST /api/assets/statuses` | `machinestatus` -> `status` | `status` |
-| `relationshiptypes` | `POST /api/assets/relationshiptypes` | `relationshiptype` -> `relationshiptype`, `description` | `relationshiptype` |
+| `relationshiptypes` | `POST /api/assets/relationshiptypes` | `relationshiptype` -> `relationshiptype`, `description`, `isdirectional` (bool, default true; false = symmetric connection) | `relationshiptype` |
 | `notificationtypes` | `POST /api/notifications/types` | `typename`, `typedescription`, `typecolor` | `typename` |
 | `pctype` | `POST /api/computers/types` | `typename` -> `computertype`, `description` | `computertype` |
 | `subnettypes` | (see subnets) | used as `subnettype` string on subnets | - |
@@ -286,6 +292,18 @@ USB devices and their history:
 
    The `checkouttime`/`checkintime` overrides are honored only in import mode.
 
+Employee directory (people): only self-hosted mode (`employee_directory_mode =
+selfhosted`) owns people in this app; import them via the directory bulk-upsert
+`POST /api/employees/directory/import` (CSV headers `SSO,First_Name,Last_Name,
+Team,Role,Picture`) or per-person `POST /api/employees/directory`. Photos:
+
+- External mode: the photo is a URL/relative path supplied by the HR database
+  (`Picture` column); it is a read-only pass-through and cannot be uploaded here.
+- Self-hosted mode: the `Picture` CSV field is a legacy text label and does not
+  drive the displayed photo. Upload the real photo after import via
+  `POST /api/employees/<sso>/photo` (multipart `file`, png/jpg/jpeg/gif/webp),
+  which stores it under `instance/employeephotos/` and serves it publicly.
+
 ### 3.7 Anything unmappable -> custom fields
 
 For a legacy column with no target field (for example `machines.logicmonitorurl`,