CB-WP-0042 T01-T04: H2's scoped stress, with the named defects caught

H2 is ground-game's answer to our H1 reading — that a flat +1 to every
seat is a solve-rate tax scaling with the number of Problems. Unclaimed
Problems now tick only the seats in scope: global (all), personal (the
owner), bond (the owner's Bond network over Bond edges only, degree 0
falling back to personal), assigned by hidden priority so 2p never has the
bond card in play.

T01: the package is vendored with digests, and H2's Problems.csv is r0's
with one column added and NOTHING else changed — checked, not assumed,
because the delta claims deal_and_thresholds unchanged and a silent
difference would make every H2-vs-baseline comparison a comparison of two
boards as well as two rule sets. Scopes are read from the column, not
derived from the priority in Rust: F25 exists because we hardcoded numbers
the edition already carried.

T02: owner and scope are new ProblemState fields, both Option and both
skipped when None, so a baseline state serialises without them and every
recorded scenario's hash is untouched — asserted on the JSON, not assumed.
with_variant() replaces the bare field write, because state.variant = v
would leave owners unassigned: a silently wrong game rather than a failing
one.

T03: every named defect is mutation-proven — traversing Rivalry edges,
applying stacking once, a degree-0 owner ticking everyone, personal
hitting everyone. The degree-0 mutation MISSED first: the fallback lives
inside bond_network and the mutation broke the None-owner arm instead, a
different branch. It stayed green until aimed at the path the test
exercises. A mutation that misses is not evidence the test works.

T04: ownership is not a permission. Filtering SOLVE to the owner turns it
red, which is the regression this task exists for — the engine had no
owner concept before T02 added one.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

workplans/CB-WP-0042-h2-scoped-problem-stress.md

@@ -2,7 +2,7 @@
 id: CB-WP-0042
 kind: product
 title: "H2 — scoped problem stress"
-status: ready
+status: active
 state_hub_workstream_id: "8f11d55b-3452-49f3-9857-d0bf06752f68"
 ---
 
@@ -57,7 +57,7 @@ do not have:
 
 ```task
 id: CB-WP-0042-T01
-status: todo
+status: done
 priority: high
 state_hub_task_id: "37f9bc34-05d1-4a12-9a98-6c61ab3ec23f"
 ```
@@ -74,11 +74,20 @@ state_hub_task_id: "37f9bc34-05d1-4a12-9a98-6c61ab3ec23f"
   state and ours to read**, and F25 exists because we hardcoded numbers
   the edition already carried.
 
+**Done 2026-08-08.** Package vendored with digests; `edition-check` walks
+it. `StressScope` and `stress_scopes()` read the column.
+
+**H2's `Problems.csv` is r0's with one column added and nothing else
+changed** — same rows, values, suits, visibilities and priorities. That is
+**checked, not assumed**: the delta claims `deal_and_thresholds` unchanged,
+and a silent difference would make every H2-vs-baseline comparison a
+comparison of two boards as well as two rule sets.
+
 ## Task: ownership at setup
 
 ```task
 id: CB-WP-0042-T02
-status: todo
+status: done
 priority: high
 state_hub_task_id: "65b9b2b8-8160-488f-8cd4-b7f734d03b22"
 ```
@@ -96,11 +105,21 @@ starting at Lead, stepping clockwise. Global Problems have no owner.
   because the assignment walks two sequences at once and off-by-one is
   the obvious failure.
 
+**Done 2026-08-08.** `owner` and `scope` on `ProblemState`, both
+`Option`, both `skip_serializing_if = "Option::is_none"` — so a baseline
+state serialises **without them** and every recorded scenario's hash is
+untouched. Asserted directly, on the JSON.
+
+**`with_variant()` replaces the bare field write.** `state.variant = v`
+would leave owners unassigned — **a silently wrong game rather than a
+failing one** — so the builder applies the variant's setup and every
+driver path goes through it.
+
 ## Task: scoped pressure
 
 ```task
 id: CB-WP-0042-T03
-status: todo
+status: done
 priority: high
 state_hub_task_id: "8426e79c-579e-4aba-a695-381020016206"
 ```
@@ -118,11 +137,26 @@ ordering H1-A needed, and the same trap.
 - **degree 0 falls back to personal**, which is the branch a test forgets;
 - ordering asserted as in CB-WP-0038: pressure before the arm check.
 
+**Done 2026-08-08.** All four named defects mutation-proven:
+
+| mutation | caught by |
+|---|---|
+| traverse Rivalry edges too | `h2_bond_scope_does_not_traverse_rivalry` |
+| stacking applied once | `h2_pressure_stacks_per_problem` |
+| degree-0 owner ticks everyone | `h2_a_bond_problem_with_no_bonds_is_personal` |
+| personal hits everyone | `h2_pressure_reaches_only_the_scope` |
+
+**The degree-0 mutation missed first**, and that is worth recording: the
+fallback lives *inside* `bond_network`, and the first mutation broke the
+`None`-owner arm instead — a different branch. It stayed green until the
+mutation was aimed at the path the test actually exercises. **A mutation
+that misses is not evidence the test works.**
+
 ## Task: SOLVE is not restricted by scope
 
 ```task
 id: CB-WP-0042-T04
-status: todo
+status: done
 priority: medium
 state_hub_task_id: "6606cb3b-733d-486c-9e46-37a2a2b0c2c9"
 ```
@@ -135,6 +169,9 @@ true — which makes it a **regression test, not a feature**. T02 adds
 ownership, and the risk is that ownership silently becomes a permission.
 The test must fail if it does.
 
+**Done 2026-08-08**, and it does: filtering SOLVE to the owner in
+`legal_commands` turns it red.
+
 ## Task: measure, and report what fails
 
 ```task