G3P-22238: honor osThreadZone() in osThreadNew (FreeRTOS shim)

[nickfritz33]

Summary

• Patches osThreadNew() in cmsis_os2.c to honor osThreadZone(N) bits in osThreadAttr_t.attr_bits. When the valid bit is set, the wrapper extracts the 6-bit zone ID, calls the application-provided ZoneGetTaskRegions(zone) to fetch a pointer to the zone's per-task MPU regions (rows 5–7 of the application's global zone table), translates each ARM_MPU_Region_t (RBAR/RLAR) into FreeRTOS's MemoryRegion_t (base/length/parameter flags), builds TaskParameters_t, and routes through xTaskCreateRestrictedStatic instead of xTaskCreateStatic.
• Strictly opt-in: tasks without osThreadZone() in their attr_bits fall through the existing xTaskCreateStatic path unchanged. No behavior change for any existing task.
• Mirrors the existing PATCH REQUIRED comment style used for the opt-in privilege patch — if cmsis_os2.c is regenerated or the middleware package is upgraded, the block (and the matching code path in osThreadNew) must be re-applied.
• Designed to be FuSa-RTS migration-clean: application code, zone table, and osZoneSetup_Callback() are unchanged across runtimes; only this shim disappears at migration when FuSa's runtime implements zone enforcement natively.

The companion change in the Gen3-Panel main repo lives on nick/G3P-22238/create-unprivileged-task — it introduces zones.{h,c} (providing ZoneGetTaskRegions) and converts CounterTask to use osThreadZone(ZONE_UNPRIVILEGED_STUB). That branch is not slated for merge in its current form.

JIRA: G3P-22238

Test plan

Verified on Branch-Production hardware (STM32H573):

• Build is clean (configENABLE_MPU=1, configSUPPORT_STATIC_ALLOCATION=1).
• Boot is clean with no zone-using tasks (zone branch dormant; every task still hits the xTaskCreateStatic path).
• Boot is clean with CounterTask opted into osThreadZone(ZONE_UNPRIVILEGED_STUB) | osThreadUnprivileged.
• Breakpoint at CounterTaskFunc halts with CONTROL = 0x3 (nPRIV=1 unprivileged, SPSEL=1 PSP).
• MPU regions 0–3 set by FreeRTOS prvSetupMPU from linker symbols (privileged code, app code, syscalls, kernel SRAM).
• MPU region 4 set by port at the task's stack base; any-RW, no-exec.
• MPU regions 5–7 are zero, matching the empty zone-table rows for the stub zone.

Reviewer notes:

• Verify the PATCH REQUIRED comment style and placement match the convention used for the existing opt-in privilege patch (lines ~590).
• Confirm the RBAR/RLAR → MemoryRegion_t translation (AP, XN, ATTR_INDEX) round-trips correctly through vPortStoreTaskMPUSettings in port.c.
• Confirm the cast (const uint32_t (*)[2])ZoneGetTaskRegions(zone) is acceptable for avoiding a CMSIS-Core MPU header dependency in cmsis_os2.c.

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