feat(fusion_helpdesk): identity keystone helpers, seen model, admin group

Phase 1-2: build_ticket_vals/scope/unread helpers (utils.py), fusion.helpdesk.ticket.seen read-tracking model, group_reporter_admin. 10 unit tests pass on local Community.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fusion_helpdesk/models/fusion_helpdesk_ticket_seen.py

@@ -0,0 +1,66 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1
+"""Per-user read-tracking for the embedded ticket inbox.
+
+Stores ONLY metadata — which central ticket a user has seen and up to
+which message id. No ticket content is replicated locally; this exists
+purely so the systray unread badge can work without re-fetching the
+whole inbox on every page load. Tickets themselves remain a live RPC
+view of the central Odoo.
+"""
+from odoo import api, fields, models
+
+
+class FusionHelpdeskTicketSeen(models.Model):
+    _name = 'fusion.helpdesk.ticket.seen'
+    _description = 'Fusion Helpdesk — per-user read tracking (metadata only)'
+
+    user_id = fields.Many2one(
+        'res.users', required=True, index=True, ondelete='cascade',
+        default=lambda self: self.env.uid,
+    )
+    central_ticket_id = fields.Integer(
+        string='Central Ticket ID', required=True, index=True,
+        help='helpdesk.ticket id on the central Odoo.',
+    )
+    last_seen_message_id = fields.Integer(
+        string='Last Seen Message ID', default=0,
+        help='Highest central mail.message id this user has viewed for '
+             'the ticket. Drives the unread badge.',
+    )
+
+    _user_ticket_uniq = models.Constraint(
+        'UNIQUE(user_id, central_ticket_id)',
+        'One seen-row per user per ticket.',
+    )
+
+    @api.model
+    def _mark_seen(self, central_ticket_id, last_message_id):
+        """Upsert the current user's last-seen marker for a ticket.
+
+        Monotonic — never moves the marker backwards (a stale client
+        reporting an older id can't resurrect an unread badge)."""
+        rec = self.search([
+            ('user_id', '=', self.env.uid),
+            ('central_ticket_id', '=', central_ticket_id),
+        ], limit=1)
+        if rec:
+            if (last_message_id or 0) > rec.last_seen_message_id:
+                rec.last_seen_message_id = last_message_id
+        else:
+            self.create({
+                'central_ticket_id': central_ticket_id,
+                'last_seen_message_id': last_message_id or 0,
+            })
+        return True
+
+    @api.model
+    def _seen_map(self, central_ticket_ids):
+        """Return {central_ticket_id: last_seen_message_id} for the
+        current user across the given ticket ids."""
+        rows = self.search([
+            ('user_id', '=', self.env.uid),
+            ('central_ticket_id', 'in', list(central_ticket_ids)),
+        ])
+        return {r.central_ticket_id: r.last_seen_message_id for r in rows}