docs(runtime): close J1 contract gate

Record the exact-binary connected lifecycle/reconnect acceptance, synchronized active pointers, rollback, and durable evidence before session ownership moves in J2.

docs/research/2026-07-25-slice-j1-runtime-contract-closeout.md

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+# Modern runtime Slice J1 closeout
+
+## Result
+
+Slice J1 is complete at production commit
+`854d9e9cd13092bd5aaa3cf025d73eeb4600e9f8`.
+
+`AcDream.Runtime` now defines the presentation-independent seams required
+before ownership moves:
+
+- borrowed immutable entity, inventory, chat, movement, and portal views;
+- generation-gated typed session, selection, combat, movement, chat, and
+  portal commands;
+- ordered typed deltas and normalized parity traces;
+- an instance-scoped frame/simulation clock;
+- lifecycle snapshots, generation tokens, and retryable teardown
+  acknowledgements.
+
+The App implementation is deliberately an adapter over current canonical
+owners. It does not copy mutable collections, add a command queue, own a
+second GUID map, or add a frame of input latency. Startup and press-time input
+reach the same session, selection, movement, and combat owners synchronously.
+No gameplay owner moved in J1.
+
+## Automated acceptance
+
+At the production commit:
+
+- Runtime contract tests: 13 passed;
+- App tests: 3,838 passed / 3 skipped;
+- complete Release solution: 8,424 passed / 5 skipped;
+- Release solution build: pass.
+
+The tests cover clock normalization/freeze and instance isolation, generation
+and teardown semantics, event-sequencer isolation, trace normalization,
+connected start through the adapter, borrowed live entity/inventory/chat/
+portal views, same-owner command mutation, ordered domain traces, stale
+generation rejection, and complete stop acknowledgement.
+
+## Connected lifecycle acceptance
+
+Raw evidence:
+`logs/connected-world-gate-20260725-190953/report.json`.
+
+Result: PASS on the exact production commit.
+
+- Capped process: login plus Aerlinthe, Rynthid, Facility Hub, Holtburg after
+  dungeon, and Aerlinthe revisit all completed.
+- Fresh uncapped process: reconnect completed.
+- Seven of seven checkpoints passed.
+- Both processes exited gracefully with exit code zero.
+- No gate failure was recorded.
+- The only warning was 25 expected world-edge landblock misses.
+
+This connected run proves that routing the startup command through the J1 seam
+did not alter live connection, world traversal, replacement, or shutdown
+behavior.
+
+## Exact rollback
+
+```text
+git revert 854d9e9cd13092bd5aaa3cf025d73eeb4600e9f8
+```
+
+J0 remains independently reversible with:
+
+```text
+git revert b632672e5ccabfb44c551e08f1c411ab2669c44a
+```
+