Auto PR - develop → MAPL-v3 - Remove NCCS Cascade Lake support and align FV3 timesteps

AGENTS.md

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+# AGENTS.md
+
+**Audience:** coding agents and developers working in the `FVdycoreCubed_GridComp` repository.
+**Describes:** the MAPL2 line, branch `develop`.
+**Verified against:** `FVdycoreCubed_GridComp` @ `4deed15` (2026-10-27).
+**Placement:** as in the GEOSgcm fixture (`components.yaml` @ `0f2e0fb`).
+Other fixtures (for example GEOSadas, GEOSldas) may place this repository
+elsewhere; paths inside this repository do not change.
+
+## What this is
+
+The MAPL gridded-component wrapper of the GFDL FV3 cubed-sphere dynamical core.
+In the GEOSgcm fixture it is at
+`src/Components/@GEOSgcm_GridComp/GEOSagcm_GridComp/GEOSsuperdyn_GridComp/@FVdycoreCubed_GridComp`
+(`components.yaml`, key `FVdycoreCubed_GridComp`). Its parent is
+`GEOS_SuperdynGridComp` in `GEOSgcm_GridComp`. The core itself lives in the
+nested repository `@fvdycore` (key `fvdycore`); edit it only in its own repository.
+
+## Documents
+
+Read `docs/ARCHITECTURE.md` first.
+
+| Document | Content |
+|---|---|
+| [`docs/ARCHITECTURE.md`](docs/ARCHITECTURE.md) | The `DYN` component (SetServices, Initialize, Run phases 1 and 2), `FV_StateMod`, state and restarts, tracers (`TRADV`), `ADV`, configuration keys, `@fvdycore`, `geos-gtfv3`, `scripts`, build, traps |
+| [`docs/decisions.md`](docs/decisions.md) | Previous architectural decisions (pattern, likely reason) |
+| `../../ARCHITECTURE.md` | Parent: Agcm and Superdyn run order (in `GEOSgcm_GridComp`) |
+| `README.md`, `CONTRIBUTING.md` | Project basics, contribution rules |
+
+## Where things are
+
+| Want to change | Go to |
+|---|---|
+| Component interface (imports, exports, internal state, run phases) | `DynCore_GridCompMod.F90` (module `FVdycoreCubed_GridComp`) |
+| Call into the FV3 core, tracer packing, dry mass | `FV_StateMod.F90` (`FV_Run`, `FV_Setup`) |
+| Offline tracer advection (`FV3+ADV`) | `AdvCore_GridCompMod.F90` |
+| Python gtFV3 core | `geos-gtfv3/` |
+| Standalone experiment setup, build options | `scripts/`, `CMakeLists.txt` |
+
+## Rules for changes
+
+- `DYN` has two Run phases; Superdyn copies `DUDT`, `DVDT`, `DTDT`, `DWDT` into the
+  `DYN` imports before each. Phase 1 applies the analysis/bias tendencies the Agcm
+  put there (`DO_UPDATE_ANA3D`); phase 2 applies the physics tendencies
+  (`DO_UPDATE_PHY`). Both go through `ADD_INCS`.
+- Keep exports used by `ADV` (`MFX`, `MFY`, `CX`, `CY`, `PLE0`, `PLE1`) consistent
+  with `AdvCore_GridCompMod.F90` and Superdyn.
+- *Inferred:* the tracer selection lists in `DYN` and `ADV` are separate and must
+  agree; no code checks it (`docs/ARCHITECTURE.md` section 7).
+- Tracers are not in the dycore restart; `DYN` borrows the `TRADV` bundle fields.
+- `DYN` and `ADV` share the module array `FV_Atm` of `FV_StateMod`.
+- Several `.F90` files are not in `CMakeLists.txt` (architecture document,
+  section 2); they are not compiled here. `FV_PRECISION` is set by the fixture build.
+
+## Build and test
+
+Built as part of the fixture (GEOSgcm). Tests: this repository has no unit-test
+directory; its checks are the CI jobs in `.circleci/config.yml` (`ci/build`,
+`ci/run_fv3`, `ci/run_gcm`). Executables are listed in `docs/ARCHITECTURE.md`
+section 10; standalone experiments: `scripts/fv3_setup`.