Epic: First-class watchOS support

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Epic Goal

Make watchOS a first-class SixLayer platform for a defined public API surface—not merely “unit tests compile and run.”

Relationship to test-matrix work

• Epic Run Full Test Suite for Every Platform #233 = prove the platform×layer matrix.
• Expand test coverage for non-iOS/macOS platforms (tvOS, watchOS, visionOS) #219 = truthful coverage where ViewInspector is N/A / not the right tool (watchOS unit now links ViewInspector + TestKit on next; still not a full VI product suite).
• This epic = product + API decisions and implementation for watchOS.

Do not conflate closing #219/#233 with “watchOS is fully supported.”

Platform realities (starting assumptions)

• Tiny screen, digital crown / gestures; many iOS navigation and chrome patterns do not apply.
• Prefer 26.5 simulators locally; 27.0 bootstrap has been suspect ([Epic #233] watchOS SLF-watchOS-AllTests: simulator bootstrap failure (esp. 27.0) #354 notes).
• Unit lane green in Run Full Test Suite for Every Platform #233 lineage; empty UITest runner omitted from AllTests ([Epic #233] watchOS SLF-watchOS-AllTests: simulator bootstrap failure (esp. 27.0) #354). Native XCUI remains follow-on.

Scope (living)

In scope (to be refined into child issues)

• Public API matrix for watchOS: works / stub / compile-only / N/A
• Implement or explicitly N/A each row; link children
• Acceptance tests at the cheapest truthful layer
• Docs / README: what “watchOS support” means for consumers

Out of scope (unless promoted)

• Forcing desktop/iPhone interaction models onto watch
• Triplicating shared API work already tracked for tvOS/visionOS

Shared work

Cross-platform framework changes should be linked shared children referenced from all three platform epics.

Definition of Done

• API matrix published and kept current on this issue
• Every “works” row has automated acceptance evidence (recipe: SHA, scheme, destination)
• Every N/A / stub row is documented with rationale
• Release-gate stance for watchOS is explicit
• Related Run Full Test Suite for Every Platform #233 matrix cell(s) updated to match claims

Related

• Epic Run Full Test Suite for Every Platform #233 · Coverage Expand test coverage for non-iOS/macOS platforms (tvOS, watchOS, visionOS) #219 · Sibling epics: tvOS / visionOS (to be linked after create)

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Sibling platform epics

• tvOS: Epic: First-class tvOS support #376
• watchOS: Epic: First-class watchOS support #377
• visionOS: Epic: First-class visionOS support #378

Also: test matrix epic #233, coverage #219.

Shared framework work that unblocks more than one platform should be a linked shared child, not duplicated under each epic.

[schatt]

#394 now tracks watchOS host + native XCUI (itemized excluded UITest sources). #354 only omitted the empty runner.