fix: use date strings for mark attendance date

[nareshkannasln]

Description:
In the Mark Attendance dialog, the Start and End date fields set their defaults to native JS Date objects via moment().toDate(). Frappe's Date control expects a string.

Error Log: {
"exception": "frappe.exceptions.ValidationError: Wed Jul 01 2026 00:00:00 GMT+0530 (India Standard Time) is not a valid date string.",
"exc_type": "ValidationError",
"_exc_source": "hrms (app)",
"exc": "["Traceback (most recent call last):\n File \"apps/frappe/frappe/utils/data.py\", line 139, in getdate\n return datetime.date.fromisoformat(string_date)\n ~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^\nValueError: Invalid isoformat string: 'Wed Jul 01 2026 00:00:00 GMT+0530 (India Standard Time)'\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n File \"apps/frappe/frappe/utils/data.py\", line 142, in getdate\n return parser.parse(string_date, dayfirst=parse_day_first).date()\n ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n File \"env/lib/python3.14/site-packages/dateutil/parser/_parser.py\", line 1368, in parse\n return DEFAULTPARSER.parse(timestr, **kwargs)\n ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^\n File \"env/lib/python3.14/site-packages/dateutil/parser/parser.py\", line 643, in parse\n raise ParserError(\"Unknown string format: %s\", timestr)\ndateutil.parser.parser.ParserError: Unknown string format: Wed Jul 01 2026 00:00:00 GMT+0530 (India Standard Time)\n\nDuring handling of the above exception, another exception occurred:\n\nTraceback (most recent call last):\n File \"apps/frappe/frappe/app.py\", line 125, in application\n response = frappe.api.handle(request)\n File \"apps/frappe/frappe/api/init.py\", line 64, in handle\n data = endpoint(**arguments)\n File \"apps/frappe/frappe/api/v1.py\", line 46, in handle_rpc_call\n return frappe.handler.handle()\n ~~~~~~~~~~~~~~~~~~~~~^^\n File \"apps/frappe/frappe/handler.py\", line 54, in handle\n data = execute_cmd(cmd)\n File \"apps/frappe/frappe/handler.py\", line 87, in execute_cmd\n return frappe.call(method, **frappe.form_dict)\n ~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n File \"apps/frappe/frappe/init.py\", line 1139, in call\n return fn(*args, **newargs)\n File \"apps/frappe/frappe/utils/typing_validations.py\", line 49, in wrapper\n return func(*args, **kwargs)\n File \"apps/hrms/hrms/hr/doctype/attendance/attendance.py\", line 440, in get_unmarked_days\n from_date = max(getdate(from_date), joining_date or getdate(from_date))\n ~~~~~~~^^^^^^^^^^^\n File \"apps/frappe/frappe/utils/data.py\", line 144, in getdate\n frappe.throw(\n ~~~~~~~~~~~~^\n \tfrappe.(\"{} is not a valid date string.\").format(frappe.bold(string_date)),\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n \ttitle=frappe.(\"Invalid Date\"),\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n )\n ^\n File \"apps/frappe/frappe/utils/messages.py\", line 159, in throw\n msgprint(\n ~~~~~~~~^\n \tmsg,\n ^^^^\n ...<7 lines>...\n \tallow_dangerous_html=allow_dangerous_html,\n ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n )\n ^\n File \"apps/frappe/frappe/utils/messages.py\", line 118, in msgprint\n _raise_exception()\n ~~~~~~~~~~~~~~~~^^\n File \"apps/frappe/frappe/utils/messages.py\", line 59, in _raise_exception\n raise exc\nfrappe.exceptions.ValidationError: Wed Jul 01 2026 00:00:00 GMT+0530 (India Standard Time) is not a valid date string.\n"]",
"_server_messages": "["{\"message\":\"Wed Jul 01 2026 00:00:00 GMT+0530 (India Standard Time) is not a valid date string.\",\"as_table\":false,\"title\":\"Invalid Date\",\"indicator\":\"red\",\"raise_exception\":1,\"__frappe_exc_id\":\"82565168f842d132551438938311a247cfb479d614e72c211d50d3b9\"}"]"
}

Before:

Screencast.from.2026-07-16.19-10-02.webm

After:

Screencast.from.2026-07-16.18-45-23.webm

Backport needed for v15, v16

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[greptile-apps]

Confidence Score: 5/5

Safe to merge — two-line targeted fix that correctly converts moment objects to ISO date strings for Frappe's Date control.

The change is minimal and directly addresses the documented error. frappe.datetime.obj_to_str is the standard Frappe utility for this conversion, and the fix applies symmetrically to both date fields.

No files require special attention.

_{Reviews (1): Last reviewed commit: "chore: update date string with obj_to_st..." | Re-trigger Greptile}