feat(fusion_login_audit): nightly retention GC cron

Adds _fc_retention_gc() that deletes rows older than the configured
horizon (default 365 days; 0 = keep forever). Registered as a daily
ir.cron. Tests verify both the delete path and the "keep forever"
short-circuit.

Also documents the Odoo 19 gotcha that ir.cron dropped the numbercall
field (the legacy "-1 = run forever" pattern now raises ValueError at
install time; just omit the field).

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

CLAUDE.md

@@ -27,6 +27,8 @@
    The attribute name after the leading underscore becomes the SQL object name suffix (`{table}_{suffix}`). `models.Index` accepts `DESC`, `WHERE` predicates, and `USING btree (...)`. Sources: `odoo/orm/model_classes.py` (warns at registry build), `odoo/orm/table_objects.py` (Constraint + Index classes).
 10. **`res.users._login` is an instance method in Odoo 19**, not a classmethod as in earlier versions. Signature is `def _login(self, credential, user_agent_env)` — there is no `db` parameter. Override it like any normal instance method (`super()._login(credential, user_agent_env)`). When called via `authenticate()` on an empty recordset, `self` carries the right env. Older recipes that build a separate `api.Environment` from `odoo.modules.registry.Registry(db)` no longer apply. Source: `odoo/addons/base/models/res_users.py:760`.
 11. **Inherited `ir.ui.view` records cannot have `groups`/`group_ids` on the record itself.** Odoo 19 raises `ParseError: Inherited view cannot have 'groups' defined on the record. Use 'groups' attributes inside the view definition` at install time. Move the gate to the inner XML nodes — every `<button>`, `<page>`, `<field>`, `<xpath>`, `<group>` etc. supports a `groups="base.group_system"` attribute. For an inherited form with a smart button + admin tab, put `groups=` on the button and the page individually; leave the `<record model="ir.ui.view">` clean.
+12. **`mail.template` QWeb/inline_template `ctx` IS `self.env.context`** — not a nested dict you can pass. `MailRenderMixin._render_eval_context()` sets `ctx = self.env.context`, so `ctx.get('foo')` in subject/body resolves to `env.context.get('foo')`. To pass dynamic data to a template, spread keys directly into the context: `tmpl.with_context(**my_data).send_mail(res_id, ...)`. Calling `tmpl.with_context(ctx=my_data)` puts the dict at `env.context['ctx']`, and the template's `ctx.get('foo')` becomes `env.context.get('foo')` → `None` (looks like a silent rendering bug — subject ends up blank).
+13. **`ir.cron` dropped `numbercall`** in Odoo 19. Old recipes set `<field name="numbercall">-1</field>` for "run forever"; that now raises `ValueError: Invalid field 'numbercall' in 'ir.cron'` at install time. Just omit the field — recurring crons keep running as long as `active=True`. Source: `odoo/addons/base/models/ir_cron.py` field list.
 
 15. **There is NO `sale.subscription` model in Odoo 19** (Enterprise `sale_subscription`). A subscription is a **`sale.order`** with `is_subscription=True`, `plan_id` → **`sale.subscription.plan`** (the recurrence), plus `subscription_state` / `next_invoice_date` / `recurring_monthly`. Any Many2one or relation that targets "a subscription" must point at `sale.order` (filter `domain=[('is_subscription','=',True)]`) — **not** `sale.subscription`, which does not exist and fails at install. The surviving `sale.subscription.*` records are only the plan + wizards/reports (`sale.subscription.plan`, `sale.subscription.report`, `sale.subscription.change.customer.wizard`, `sale.subscription.close.reason.wizard`). Verified on live `nexamain` (odoo-nexa, 19.0): `SELECT model FROM ir_model WHERE model LIKE 'sale.subscription%'`.