fix(gps): make acquisition and reacquisition deterministic

soc/software/gps_system/Makefile

@@ -6,6 +6,7 @@ TARGET := gps_system
 # UART image.
 GPS_DEBUG ?= 1
 GPS_DEBUG_LEVEL ?= 4
+GPS_BUILD_ID ?= $(shell git describe --always --dirty --abbrev=12 2>/dev/null || printf unknown)
 
 # The current Genesys2 Rocket/fabric domain that clocks the UART is 50 MHz.
 # The 50 Hz fused-location stream plus GPS diagnostics does not fit safely in
@@ -65,6 +66,8 @@ APP_SRCS := \
 	src/adapters/gps_fusion_publisher.c \
 	src/gps/gps_ip.c \
 	src/gps/gps_interrupt_handlers.c \
+	src/gps/gps_acq_manager.c \
+	src/gps/gps_ephemeris_cache.c \
 	src/gps/gps_time_anchor.c \
 	src/gps/gps_nav_epoch.c \
 	src/gps/gps_pps.c \
@@ -80,6 +83,7 @@ include ../common/app.mk
 
 CFLAGS += -Iheader
 CFLAGS += $(IMU_BACKEND_CFLAG) \
+	-DGPS_BUILD_ID=\"$(GPS_BUILD_ID)\" \
 	-DIMU_ODR_HZ=$(IMU_ODR_HZ) \
 	-DIMU_ACCEL_FS_G=$(IMU_ACCEL_FS_G) \
 	-DIMU_GYRO_FS_DPS=$(IMU_GYRO_FS_DPS) \