feat(package): session packages backed by a credit ledger

"Six laser sessions" is the common case in an aesthetics clinic: the patient
pays once and books the sessions later.

Credit is a ledger, not a counter. No table has a remaining/used_count column
and a schema test enforces that — the balance is always SUM(delta) over
append-only rows, so every number a patient sees has a full history behind it.
Corrections are new rows, never edits.

- purchase / consume / refund / adjustment / expiry, each with a reason, an
  author and the appointment it belongs to
- consume happens in confirm(), never in quote(): if the preview consumed, a
  page refresh would cost the patient a session
- cancelling adds a refund row; the consume row stays
- FIFO across a patient's packages — the oldest is closest to expiring
- an empty package is not an error, it just does not apply and the patient pays
- adjust/expire need a doctor or clinic role, and adjust always needs a reason
- app:package:expire writes the closing row so "where did my 3 sessions go?"
  always has an answer

Consume takes a pessimistic lock on the one package row. That is the opposite
of task 07's slot buckets, and docs/api/package.md carries the table explaining
why, so nobody unifies them later.

Idempotency checks for an existing consume row before inserting rather than
catching the unique violation: in Doctrine that exception closes the
EntityManager and burns the rest of the request. The unique key stays as the
last line of defence.

Admin: PackagesPage, a packages tab on the patient record, and a ledger page
whose running-balance column shows where the final number came from.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

docs/architecture/tenancy.md

@@ -305,3 +305,13 @@ php bin/console app:tenant:dump --tenant=clinic:12 --output=/tmp/clinic12.sql
 | `tests/Patient/PatientWalletTenantTest.php` | دفتر کیف پول per-محیط است ولی موجودی سراسری می‌ماند |
 | `tests/Shared/RequestReachableChildTenantTest.php` | فرزندانِ قابل‌دسترس با uuid را **خودِ فیلتر** می‌بندد، بدون گارد دستی |
 | `tests/Auth/MultiClinicOwnerContextTest.php` | مالک چند کلینیک به هرکدام می‌تواند سوییچ کند |
+
+
+## اعتبار جلسه: چرا برخلاف کیف پول جفت محیط می‌گیرد
+
+`wallet_transactions` عمداً در `ENTITIES` است: پول مالِ **شخص** است و در هر محیطی همان
+پول است؛ هر ردیف فقط `recorded_entity_*` دارد تا معلوم باشد کجا ثبت شده.
+
+`session_credit_ledger` متفاوت است و جفت محیط واقعی می‌گیرد: «شش جلسه لیزر کلینیک الف»
+در کلینیک ب هیچ معنایی ندارد و قابل مصرف نیست. همین تفاوت باعث می‌شود پکیج‌های یک بیمار
+در دو کلینیک کاملاً از هم جدا بمانند.