[19.0][MIG] account_statement_import_online_mercury: Migration to 19.0

[dnplkndll]

Migrates account_statement_import_online_mercury (#910) to 19.0.

Depends on #910 ([18.0][ADD] account_statement_import_online_mercury).
When #910 merges, the [BOT] post-merge updates commit in this PR will be
rebased to match the bot's actual replay.

Migration changes ([19.0][MIG] commit)

• Bump manifest to 19.0.1.0.0.
• Modernise translations per pylint_odoo 19.0 (W8161 prefer-env-translation
  • W8301 translation-not-lazy): replace from odoo import _ and
    _("...%(x)s") % {"x": x} with self.env._("...%(x)s", x=x).

No other 19.0 API breakage in this module — no _sql_constraints, auto_join,
groups_id, or odoo.osv.expression usage.

Tests

20 tests pass locally on Odoo 19.0:

$ docker compose run --rm odoo-19 odoo -d odoo19_base \\
    -i account_statement_import_online_mercury \\
    --stop-after-init --no-http --test-enable
Module account_statement_import_online_mercury loaded in 0.66s
0 failed, 0 error(s) of 20 tests

CI on the branch is also green:

• pre-commit ✅
• ruff / ruff format ✅
• pylint_odoo ✅
• prettier (XML) ✅

/ocabot migration account_statement_import_online_mercury