e1608: do not fight a hardware trigger, stop the scan on a failed connect, daemon drop timer in the mock

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/claude/architecture.md

@@ -48,7 +48,7 @@ What feeds `Acquisition` is a `DataSource`, one of the registered *kinds*.
   `e1608_source` is the `DataSource`; `e1608_kind` and `e1608_panels` are the UI. A change to the wire
   never reaches the UI files.
 - The E-1608 source runs **everything inside `poll()`** on the producer thread: posted commands, the
-  connect state machine (Down, Scanning, Halted), the scan read, the 500 ms status check, the digital
+  connect state machine (Down, Scanning, Halted), the scan read, the 500 ms status check (its not-running restart is skipped when a hardware trigger is configured), the digital
   input/counter poll and the 20 ms waveform tick. There is no second thread. A connect attempt (discovery,
   handshake, calibration read, scan start) can block `poll()` for as long as the command timeout allows each
   step; that delays only the command queue. Every exception is caught inside `poll()`: an escape would end