spp_base_common: menu-icon env.ref hook can take down a job worker on a poisoned cursor

[gonzalesedwin1123]

spp_base_common/models/ir_module_module.py's menu-icon decoration hook calls
self.env.ref(...) during registry load. Two hardening gaps:

1. env.ref without raise_if_not_found=False — a missing xmlid raises during
   registry load, which is fatal to whatever process is loading the registry.
2. No tolerance for an aborted transaction: in a recent job-worker incident, a
   UniqueViolation elsewhere poisoned the cursor, and this hook's _xmlid_lookup
   then raised InFailedSqlTransaction on every registry (re)load — repeatedly
   killing the odoo-job-worker thread until the database was quarantined
   (fix(worker): survive a job-level database error instead of quarantining the DB odoo-job-worker#22 hardened the worker side; this is the first-order
   fix). Decorating app menu icons should never be able to take a worker down.

Proposed direction: raise_if_not_found=False plus a defensive try/except around
the lookup that logs and skips decoration on any DatabaseError — cosmetic feature,
best-effort semantics. A regression test that runs the hook on a deliberately
aborted cursor and asserts registry load survives.

Scoped out of OpenSPP/odoo-job-worker#22 by its author.