[lestarch-autobot]

Describe the contribution
Replaces the plan of vendoring the 7-year-old SCH app (#9) with the standard, maintained cFS sch_lab scheduler:

1. apps/sch_lab (new submodule) — nasa/sch_lab at v7.0.1-4-gbfc82af, added like the other cFS submodules
2. Schedule table override — fprime_cfs_reference_defs/tables/cpu1_sch_lab_table.c publishes the F Prime tick (command MID 0x1890 = APID 0x090, function code 0) once per second (TickRate 100, PacketRate 100), using the cFS-recommended mission-level table override mechanism
3. Glue — sch_lab added to MISSION_GLOBAL_APPLIST and the cpu1 startup script (cFE name SCH_LAB, required to match the table name SCH_LAB.Schedule)
4. README — documents the sch_lab tick source

No changes to fprime_app are needed: its CfsBridge already subscribes to the 0x1890 tick and routes it to the SchAppDriver.

Supersedes #9 (old vendored SCH app) and the SCH-prerequisite README callout of #12.

Testing performed

1. make SIMULATION=native prep && make && make install — clean build; table override confirmed selected by the build system
2. ./core-cpu1 — SCH Lab v7.0.1 initializes, loads the table, and the F Prime rate groups cycle at 1 Hz
3. pytest test/int — all 5 GDS integration tests pass (commands, events, telemetry through GDS)

Expected behavior changes

• The F Prime rate group tree is now clocked by sch_lab; previously no app in the repo published the tick, so rate groups never cycled on devel.
• No API changes.

System(s) tested on

• Hardware: PC (x86_64)
• OS: Ubuntu 22.04 (SIMULATION=native)
• Versions: cFE 7.0.0 (Draco), sch_lab v7.0.1, pinned fprime/fprime_cfs/fprime_app/fprime_gds submodules

Additional context
sch_lab is the actively maintained scheduler pattern shipped with the cFS bundle; the SCH app of #9 is v2.2.1 (~7 years old) and required manual porting to current cFE APIs.

Contributor Info
Michael Starch, NASA JPL (via Devin)