Naming/contract delta: _root_cfg, _device_boundaries, blocked_coarse_tables; NODE vs EDGE frame

- Coarse/fine name the two members of any pair (Hierarchy docstring); only the
  misleading blocked_base_tables -> blocked_coarse_tables. prepare_fine_boundary
  and blocked_fine_tables keep their pair-relative names.
- Depth-1 static circles use the integer-NODE frame (unchanged behavior); the
  root EDGE frame applies to refined levels only. Contract text corrected.
- _kernel_configs documents why it stays distinct from Hierarchy.configs.
- Drop the stale re-export comment; two tests import table builders from
  refinement_tables. Mechanical caller renames for this delta only.
No numerical code or config derivation changed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/development/src_coherence.md

@@ -8,8 +8,13 @@ pending a GPU run).
 
 - Level `l = 0 .. depth-1` (0 = root). Pair `hierarchy.pairs[l-1]` builds level `l`.
 - Array shapes are `(ny, nx)`; rectangles, origins and centers are `(x, y)`.
-- FixedPatchStepper bodies/Jets use the root EDGE frame (root cell `i` = `[i, i+1)`);
-  uniform `Simulation` objects use the integer-NODE frame. Nothing converts between them.
+- Coarse/fine name the two members (parent/child) of ANY pair, not absolute L0/L1:
+  `fine_shape`, `fine_origin`, `prepare_fine_boundary`, `blocked_fine_tables`,
+  `blocked_coarse_tables`.
+- Refined levels (l >= 1) of FixedPatchStepper place bodies/Jets in the root EDGE frame
+  (root cell `i` = `[i, i+1)`). Uniform `Simulation` objects AND the static circles of a
+  single-level (depth 1) FixedPatchStepper use the integer-NODE frame. Nothing converts
+  between them.
 - `Hierarchy.edge_frame(l)` -> `((ox, oy), h)`: cell `(i, j)` of level `l`'s allocated
   array (ghost band and holes included) covers `[o + h*i, o + h*(i+1))`. A scalar
   FixedPatch2D window carries the half-coarse-cell ghost shift `bounds - HALO/2` in
@@ -26,8 +31,11 @@ pending a GPU run).
 | `base_layout`, `fine_layout`, `child_layout` (stepper properties) | `layouts[0]`, `layouts[1]`, `layouts[2]` (`FixedPatchSet2D.fine_layout(block)` is unchanged) |
 | `fine_boundary`, `child_boundary` | `boundaries[1]`, `boundaries[2]` (host geometry; `None` = no bodies/Jets) |
 | `_jets` | `jets[1]` |
-| `_boundaries[l]` (dict from L1, level keys) | `_level_boundaries[l]` (list from L0, `None` at L0 unless single-level static circles) |
-| `_fine_tables`, `_actuated`, `_jet_cache` | `_level_boundaries[1].tables` / `.actuated` / `.jet_cache` |
+| `_boundaries[l]` (dict from L1, level keys) | `_device_boundaries[l]` (list from L0, `None` at L0 unless single-level static circles) |
+| `_level_boundaries` (private, b4eacf7) | `_device_boundaries` |
+| `_fine_tables`, `_actuated`, `_jet_cache` | `_device_boundaries[1].tables` / `.actuated` / `.jet_cache` |
+| `_remap_cfg` (private) | `_root_cfg` |
+| `refinement_tables.blocked_base_tables` (also via `refinement_stepper`) | `refinement_tables.blocked_coarse_tables` (import from `refinement_tables`; the stepper no longer re-exports) |
 | `_fine_leaf`, `_child_leaf` | `leaf[1]`, `leaf[2]` (copies) |
 | `_middle_kind` | `hierarchy.kinds[1]` |
 | `_boundary_hosts` (private) | `_boundaries` (private list behind `boundaries`) |
@@ -56,6 +64,10 @@ the replaced level relative to its parent).
 
 ## Not done / open
 
+- Two per-level config derivations stay distinct on purpose: `Hierarchy.configs`
+  (`_middle_config`, wall fields reset on every refined level, geometry validation) vs.
+  `FixedPatchStepper._kernel_configs` (reset only on level 1 of a slot_reservoir root;
+  generates each level's config.h). Folding them needs a config.h/PTX diff gate.
 - No single-`Simulation` facade over FixedPatchStepper: the two own different state models
   (uniform node frame, body sync, forcing, checkpoint vs. immutable blocked hierarchy, edge
   frame, remap-as-new-instance). A facade would only forward calls; no concrete need found.