Retire the legacy Machine model (ADR-001 cutover)

The asset/computer model is now the single source of truth. Remove the Machine
instance layer end to end:

- Delete models Machine, MachineStatus, PCType, MachineRelationship,
  InstalledApp, PrinterData; keep MachineType (models.machinetypeid still
  references it).
- Delete the /api/machines, /api/statuses, /api/pctypes blueprints and the
  legacy /api/printers/legacy (PrinterData) blueprint.
- Drop the deprecated communications.machineid column and its FK.
- Migration 7c01 drops tables machines, machinestatuses, pctypes,
  machinerelationships, installedapps, printerdata (idempotent).
- Fix remaining readers (applications install counts) to ComputerInstalledApp.
- Frontend: remove dead machinesApi/statusesApi/pctypesApi wrappers; repoint
  the PC Types settings page at computer types.

143 tests pass; all asset/computer/dashboard/report/collector endpoints 200.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/printers/models/__init__.py

@@ -1,7 +1,6 @@
 """Printers plugin models."""
 
-from .printer_extension import PrinterData  # Legacy model for Machine-based architecture
-from .printer import Printer, PrinterType  # New Asset-based models
+from .printer import Printer, PrinterType  # Asset-based models
 from .model_supply import (  # data-driven model -> toner/drum/waste mapping
     ModelSupply,
     SUPPLY_TYPES,
@@ -10,9 +9,8 @@ from .model_supply import (  # data-driven model -> toner/drum/waste mapping
 )
 
 __all__ = [
-    'PrinterData',  # Legacy
-    'Printer',      # New
-    'PrinterType',  # New
+    'Printer',
+    'PrinterType',
     'ModelSupply',
     'SUPPLY_TYPES',
     'SUPPLY_COLORS',

plugins/printers/models/printer_extension.py

@@ -1,58 +0,0 @@
-"""PrinterData model - printer-specific fields linked to machines."""
-
-from shopdb.extensions import db
-from shopdb.core.models.base import BaseModel
-
-
-class PrinterData(BaseModel):
-    """
-    Printer-specific data linked to Machine table.
-
-    Printers are stored in the machines table (machinetype.category = 'Printer').
-    This table only holds printer-specific fields not in machines.
-
-    IP address is stored in the communications table.
-    Zabbix data is queried in real-time via API (not cached here).
-    """
-    __tablename__ = 'printerdata'
-
-    id = db.Column(db.Integer, primary_key=True)
-
-    # Link to machine
-    machineid = db.Column(
-        db.Integer,
-        db.ForeignKey('machines.machineid', ondelete='CASCADE'),
-        unique=True,
-        nullable=False,
-        index=True
-    )
-
-    # Windows/Network naming
-    windowsname = db.Column(
-        db.String(255),
-        comment='Windows printer name (e.g., \\\\server\\printer)'
-    )
-    sharename = db.Column(
-        db.String(100),
-        comment='CSF/share name'
-    )
-
-    # Installation
-    iscsf = db.Column(db.Boolean, default=False, comment='Is CSF printer')
-    installpath = db.Column(db.String(255), comment='Driver install path')
-
-    # Printer PIN (for secure print)
-    pin = db.Column(db.String(20))
-
-    # Relationship
-    machine = db.relationship(
-        'Machine',
-        backref=db.backref('printerdata', uselist=False, lazy='joined')
-    )
-
-    __table_args__ = (
-        db.Index('idx_printerdata_windowsname', 'windowsname'),
-    )
-
-    def __repr__(self):
-        return f"<PrinterData machineid={self.machineid}>"