Add save-slice-backed runtime fixtures

docs/README.md

@@ -67,17 +67,17 @@ Current local tool status:
 The atlas milestone is broad enough that the next implementation focus has already shifted downward
 into runtime rehosting. The current runtime baseline now includes deterministic stepping, periodic
 trigger dispatch, normalized runtime effects, staged event-record mutation, fixture execution,
-state-diff tooling, and a packed-event persistence bridge that now reaches per-record summaries and
-selective executable import.
+state-diff tooling, tracked save-slice documents for captured-runtime inputs, and a packed-event
+persistence bridge that now reaches per-record summaries and selective executable import.
 
 The highest-value next passes are now:
 
 - preserve the atlas and function map as the source of subsystem boundaries while continuing to
   avoid shell-first implementation bets
-- deepen captured-runtime and round-trip fixture coverage on top of the packed-event bridge that now
-  exists
 - widen packed-event target-family coverage only where static evidence is strong enough to support
   deterministic executable import
+- add the next imported object/context families needed to turn current parity-only packed rows into
+  executable runtime records
 - use `rrt-hook` primarily as optional capture or integration tooling, not as the first execution
   environment
 - keep `docs/runtime-rehost-plan.md` current as the runtime baseline and next implementation slice

docs/runtime-rehost-plan.md

@@ -22,12 +22,12 @@ Implemented today:
 - snapshots, state dumps, save-slice projection, and normalized state diffing already exist in the
   CLI and fixture layers
 - checked-in runtime fixtures already cover deterministic stepping, periodic service, direct trigger
-  service, snapshot-backed inputs, normalized state-fragment assertions, and imported packed-event
-  execution
+  service, snapshot-backed inputs, save-slice-backed inputs, normalized state-fragment assertions,
+  and imported packed-event execution
 
 That means the next implementation work is breadth, not bootstrap. The recommended next slice is
-captured-runtime depth plus wider packed-event target-family coverage, not another persistence
-scaffold pass.
+wider packed-event target-family coverage plus company-collection import depth, not another
+persistence scaffold pass.
 
 ## Why This Boundary
 
@@ -220,8 +220,10 @@ Current status:
   projected runtime snapshots, normalized diffs, and fixtures
 - the first decoded packed-event subset can now import into executable runtime records when the
   decoded actions fit the current normalized runtime-effect model
-- the remaining gap is broader captured-runtime and round-trip fixture depth plus wider packed
-  target-family coverage, not first-pass packed-event decode
+- tracked save-slice documents now provide a repo-friendly captured-runtime path without checking in
+  raw `.smp` binaries
+- the remaining gap is wider packed target-family coverage plus company-import depth, not
+  first-pass captured-runtime plumbing
 
 ### Milestone 4: Domain Expansion
 
@@ -352,6 +354,7 @@ The currently implemented normalized runtime surface is:
   normalized runtime-effect vocabulary with staged event-record mutation
 - save-side inspection and partial state projection for `.smp` inputs, including per-record packed
   event summaries and selective executable import
+- tracked save-slice documents plus save-slice-backed fixture loading for captured-runtime coverage
 
 Checked-in fixture families already include:
 
@@ -363,30 +366,30 @@ Checked-in fixture families already include:
 
 ## Next Slice
 
-The recommended next implementation slice is broader captured-runtime depth on top of the packed
-event bridge that now exists today.
+The recommended next implementation slice is wider packed-event target-family coverage on top of the
+captured save-slice workflow that now exists today.
 
 Target behavior:
 
-- keep the packed event bridge grounded against real captured save inputs rather than only synthetic
-  parser tests and snapshot fixtures
 - expand the executable import subset beyond the current direct-state and follow-on lanes only when
   target resolution and field semantics are statically grounded enough to preserve headless
   determinism
+- add the next imported object families needed to make currently parity-only packed rows executable,
+  starting with company-targeted effects
 - keep preserving unsupported packed rows as parity summaries instead of guessing executable meaning
 
 Public-model additions for that slice:
 
-- additional captured-save fixture material for packed event collections
 - wider target-family summaries only where imported execution can be justified by current static
   evidence
+- imported company/runtime context needed by the next packed-event target families
 - no shell queue/modal behavior in the runtime core
 
 Fixture work for that slice:
 
-- captured `.smp` or save-slice-backed fixtures that prove real packed event records survive import
-  and diff paths
-- regression fixtures that lock the current selective executable import boundary
+- save-slice-backed fixtures that prove real packed event records survive import and diff paths
+- regression fixtures that lock the current selective executable import boundary and the
+  unsupported/parity-only counts
 - state-fragment assertions that lock both packed parity summaries and imported executable records
 
 Do not mix this slice with: