trace_decoder: Forward lines containing "interrupt".
tracer: Implement proper interrupt handling.
tracer: Remove some debug spam.
tracer: Fix execution mode bit handling in swi.
tracer: Use the correct stack in rti (r25 vs r28).
tracer: Pushing sp actually pushes the value of sp after the instruction.
tracer: 16-bit ld/st relative to sp has an unsigned offset.
_instructions.yaml: Fix various instruction descriptions.
tracer: Properly implement r25/r28/r27 aliasing in the different modes.