Add Pac-Man power-on flow and document Odin integration

- Add a four-second arcade-style boot sequence followed by the
  Character / Nickname introduction.
- Separate cabinet power-on from RFID credit and player Start.
- Add operator Power on control and cabinet power-state reporting.
- Prevent repeated power commands from restarting boot or gameplay.
- Ignore RFID scans received before the cabinet is ready.
- Add power-state, RFID, controller, and GPIO feedback regression tests.

- Expand the master walkthrough with export, packaging, file transfer,
  fresh-Pi setup, RFID compilation, and end-to-end testing instructions.
- Correct tester hardware documentation: BCM23/J20 drives an LED;
  physical buttons connect through a separate I2C1 input board.
- Document operator-triggered power-on as the current test workflow
  and retain the temporary 2.4 configuration compatibility notes.
- Record successful physical testing of power-on, RFID credit,
  and player Start.

- Add an Odin integration README describing the proposed Rust/NATS
  bridge, shared messages, Flutter GM interface, autopilot sequencing,
  hardware ownership, and Starfish SSH-management role.
- Define migration milestones and information needed from the
  framework owner; link the integration guide from the root README.

Validation: 69 controller tests, 10 GPIO tests, Pac-Man power/RFID
checks, managed-cabinet lifecycle checks, and visual screen inspection.

tools/pi_gpio/device_feedback.py

@@ -59,7 +59,7 @@ class Feedback:
             old.update(value=value,error=error,stamp=self.clock())
             if changed:
                 self.sequence+=1
-                self.events.append(dict(id=self.boot+':'+str(self.sequence),device=ident,value=value,error=error,kind=old['kind']))
+                self.events.append(dict(id=self.boot+':'+str(self.sequence),device=ident,value=value,error=error,kind=old['kind'],stamp=self.clock()))
     def _readers(self, readers):
         slots={int(d['port'][1:])-1:d['id'] for d in readers}
         try:
@@ -88,7 +88,7 @@ class Feedback:
     def snapshot(self):
         with self.lock:
             now=self.clock()
-            return dict(devices=[{k:v for k,v in d.items() if k!='stamp'}|{'age_ms':int(max(0,now-d['stamp'])*1000)} for d in self.values.values()],events=list(self.events))
+            return dict(devices=[{k:v for k,v in d.items() if k!='stamp'}|{'age_ms':int(max(0,now-d['stamp'])*1000)} for d in self.values.values()],events=[{k:v for k,v in e.items() if k!='stamp'}|{'age_ms':int(max(0,now-e['stamp'])*1000)} for e in self.events])
     def close(self):
         self.stop.set()
         if self.reader: