refactor(contracts): expand additive capability facts to the keyboard, gesture and clipboard families

[thymikee]

Wave 2 child of #2409. Continues #2412 (pilot merged as #2420, edbd96ea30). The pilot's stop rule passed with seven unsupported-owner edits avoided against a floor of two, so expansion is authorized on the same terms, one family per PR.

Purpose

Adding a capability to one platform stops forcing edits in the platforms that do not support it, for the next families where owners still write a denial out cell by cell.

Baseline

On main at 41e2633f10:

• The touch family is additive. TouchRuntimeOperationFactsInput.unsupported is a required family-level denial (packages/contracts/src/touch-runtime.ts:88), every operation input is optional, and declared(fact) = fact ?? input.unsupported (:103). An owner that leaves an operation blank gets the family's typed denial with the same reason and hint it would have written by hand.
• Every other multi-operation family is required-per-operation: keyboardRuntimeOperationFacts (packages/contracts/src/keyboard-runtime.ts:46, 3 operations), gestureRuntimeOperationFacts (gesture-runtime.ts:74, 5), clipboardRuntimeOperationFacts (clipboard-runtime.ts:48, 2), plus alert (4), snapshot (3), selector-observation (2), perf (7), audio-probe (4), application-lifecycle (9).
• Owners that write a whole family as unavailable today, cell by cell:
  • keyboard: web (packages/platform-web/src/runtime.ts:416), webdriver (packages/provider-webdriver/src/platform-runtime.ts:568, raw keys without the builder), vega (packages/platform-vega/src/runtime.ts:203, raw keys). harmonyos implements 2 of 3.
  • gesture: vega (packages/platform-vega/src/runtime.ts:236), web (packages/platform-web/src/runtime.ts:401).
  • clipboard: harmonyos, web, vega.
• PR refactor(contracts): additive capability facts pilot on touch family #2420's replay of an Apple-only touch operation: 16 files / 8 packages before, 5 files / 2 packages after.

Required work

One PR per family, in this order: keyboard, gesture, clipboard.

1. Give the family builder the touch shape: a required unsupported cell on the input, optional per-operation inputs, declared(fact) = fact ?? input.unsupported. Owners that write raw keys (webdriver and vega for keyboard) move to the builder in the same PR, so the family has one entry point.
2. Owners that implement nothing in the family supply only unsupported; owners that implement part of it omit the rest. Reasons and hints are unchanged: the admission tests that assert each non-supporting platform's unavailable reason stay green with no edits.
3. Replay a single-platform addition on the new shape (add one operation to the family, implemented by one platform, the way refactor(contracts): additive capability facts pilot on touch family #2420 replayed tapElementSelector). Record in the PR body the files the compiler forces before and after, and the count of unsupported-owner edits avoided.
4. Stop rule per family: fewer than two unsupported-owner edits avoided means that family is not merged. Post the measurement here and move to the next family.
5. Keep the guard PR refactor(contracts): additive capability facts pilot on touch family #2420 restored after its first pass: an owner cannot lose an explicit cell silently. The family's exhaustive test (keyboard-runtime.test.ts and siblings) asserts the full fact shape for a fully-declared owner and for an unsupported-only owner.

Acceptance, measurable from git

• Per family: the replayed addition touches contracts, the one implementing platform package, and tests. The other platform and provider packages are untouched.
• Per family: unsupported-owner edits avoided ≥ 2, recorded in the PR body.
• Typed denial unchanged: no edit in any test that asserts an unavailable reason for a non-supporting platform.
• Umbrella metric, measured with the frozen script on refactor: cut the layers and files one feature change must touch (successor to #2278 and #2335) #2409: feat+fix commits touching ≥ 2 packages ≤ 10% over the first 100 feat+fix commits after the last family merges.

Non-goals

• Blanket defaults across all families. The remaining six multi-operation families (alert, snapshot, selector-observation, perf, audio-probe, application-lifecycle) wait for this issue's measurements.
• A default that hides an unclassified capability or implies success.
• Single-operation families; there is nothing to make additive.

Dependencies

None. Builds on #2420 (edbd96ea30).

[thymikee]

Keyboard family: measured (#2443 items 3-4)

PR: #2459 (branch claude/2443-additive-families, commit 880c9f4367).

Replayed addition: keyboardCommitIme — one keyboard operation named by exactly one owner, the way #2420 replayed tapElementSelector. Measured as the files that must change until pnpm typecheck is green again, applied identically to origin/main (3bbeb61917) and to the branch.

shape	files	packages	unsupported-owner edits
old (required cell per operation)	25	9	17
new (unsupported + optional cells)	8	2	0

The 8 files on the new shape: packages/contracts/src/{keyboard-runtime.ts,interactor-types.ts,runtime-operation-names.ts,interactor-operation-catalog.ts,interactor-operation-conformance.test.ts,keyboard-runtime.test.ts} and packages/platform-apple/src/{navigation/runtime.ts,runner-demand.ts}. The first five plus the family's own exhaustive test are the addition itself; runner-demand.ts is Apple's total operation→host map (facts-free, forced on both shapes).

The 17 unsupported-owner edits that disappear:

Owner/shared-record fact cells (9): packages/platform-apple/src/navigation/runtime.ts, platform-harmonyos/src/runtime.ts, platform-linux/src/runtime.ts, platform-vega/src/runtime.ts, platform-web/src/runtime.ts, provider-limrun/src/interaction-operations.ts, provider-limrun/src/app-log-runtime.ts, provider-webdriver/src/platform-runtime.ts, contracts/src/platform-runtime-unavailable.ts.

Cell-enumerating test doubles (8): contracts/src/platform-runtime-unavailable.test.ts, src/__tests__/test-utils/runtime-operation-facts.ts, src/daemon/__tests__/keyboard-runtime.test.ts, src/daemon/handlers/__tests__/{install-source,session-selector-dispatch,session-state}.test.ts, src/platform-runtime-gateway.test.ts, test/integration/provider-scenarios/provider-device-runtime.fixtures.ts.

Typed denial unchanged: no edit in any test asserting a non-supporting platform's unavailable reason. The old shape was measured with the Android leg as the implementing owner; the forced set is identical whichever single owner implements, because on that shape every owner's builder call is required regardless.

Stop rule: 17 avoided ≥ 2 → keyboard merges. Gesture and clipboard follow in this order.

[thymikee]

Gesture family: measured (#2443 item 3, family 2 of 3)

PR: #2460 (branch claude/2443-gesture-facts, commit 2fa4b7eaeb, stacked on #2459).

Replayed addition: performEdgeSwipePlan — one gesture tier named by exactly one owner (Apple), applied identically to the parent head 880c9f4367 and to the gesture branch. The tier rides the family's one executor, so only the admission surface grows.

shape	files	packages	unsupported-owner edits
old (required cell per tier)	15	9	10
new (unsupported + optional tiers)	5	2	0

Files on the new shape: packages/contracts/src/{gesture-runtime.ts,runtime-operation-names.ts,gesture-runtime.test.ts} and packages/platform-apple/src/{gesture-facts.ts,runner-demand.ts}.

The ten unsupported-owner edits that disappear: the shared unavailable record (contracts/src/platform-runtime-unavailable.ts), the seven owner fact cells (platform-android, platform-harmonyos, platform-linux, platform-vega, platform-web, provider-webdriver, provider-limrun), and the two cell-enumerating test doubles (src/__tests__/test-utils/runtime-operation-facts.ts, src/daemon/handlers/__tests__/install-source.test.ts).

Typed denial unchanged: no test asserting a non-supporting owner's unavailable reason was edited.

Stop rule: 10 avoided >= 2 -> gesture merges. Clipboard is next.

[thymikee]

Clipboard family: measured (#2443 items 3-4, family 3 of 3)

PR: #2464 (branch claude/2443-clipboard-facts, commit 5738d3918a, stacked on #2460).

Replayed addition: readClipboardHtml — one clipboard operation named by exactly one owner, the Linux desktop. Unlike the keyboard and gesture replays this one grows the operation vocabulary: an optional Interactor method, a catalog row, an operation name, an operation-to-host row, and the family's conformance table are forced on both shapes and are counted as the addition, not as owner churn.

shape	files	packages	unsupported-owner edits
old (required cell per half)	23	9	15
new (unsupported + optional halves)	8	3	0

Files on the new shape: packages/contracts/src/{clipboard-runtime.ts,clipboard-runtime.test.ts,interactor-types.ts,interactor-operation-catalog.ts,interactor-operation-conformance.test.ts,runtime-operation-names.ts}, packages/platform-linux/src/runtime.ts, packages/platform-apple/src/runner-demand.ts.

The fifteen unsupported-owner edits that disappear:

• Shared unavailable record (2): contracts/src/platform-runtime-unavailable.ts and contracts/src/platform-runtime-unavailable.test.ts. On the old shape the record carried a clipboard key per half, so every record consumer pays for a new clipboard operation.
• Owner and provider cells (8): platform-android/src/runtime.ts, platform-apple/src/system/runtime.ts, platform-harmonyos/src/runtime.ts, platform-vega/src/runtime.ts, platform-web/src/runtime.ts, provider-webdriver/src/platform-runtime.ts (record cell plus the builder cell), provider-limrun/src/interaction-operations.ts, provider-limrun/src/app-log-runtime.ts.
• Cell-enumerating test doubles (5): src/__tests__/test-utils/runtime-operation-facts.ts, src/daemon/handlers/__tests__/{install-source,session-clipboard,session-state}.test.ts, src/platform-runtime-gateway.test.ts. The shared helper is the expensive one: while it enumerated the halves by hand, its absence rippled into 20 harness and handler test files before it was fixed; through the builder it costs nothing.

Typed denial unchanged: no test asserting a non-supporting owner's unavailable reason was edited, and clipboard read keeps its independent refusal from clipboard write.

Stop rule: 15 avoided >= 2 -> clipboard merges. All three families measured: keyboard 17, gesture 10, clipboard 15.