0.7.11
Fix p4_serial_smoke soak_drain stack overflow (#11).
drain_task allocated a 16 KiB local buffer on a 4096-byte FreeRTOS task stack. Buffer is now a single static 16 KiB array.
Smoke harness only. Driver streaming engine unchanged. Tag v0.7.10 is immutable.
Host tests: 225/225 passed.
Hardware: re-soak both URB images (usb_soak_960k_6x16k and usb_soak_960k_3x32k) against this tag. See docs/V0_7_11_TAB5_HANDOFF.md.