fix(ios): separate snapshot actionability from occlusion - #1933

Summary

• Make iOS snapshot geometric actionability one backend-independent predicate across recursive tree, query sweep, private AX, and collapsed-tab acquisition.
• Remove the XCTest runner later-node occlusion scan and its obsolete flatten/range/type-gate helpers while preserving intentional direct/raw interaction paths.
• Keep daemon snapshot occlusion as the sole owner of structured covered state and retain interactionBlocked: "covered" consumer behavior.
• Add focused regression coverage and changed-path live evidence for the distinction between geometric hittable and daemon occlusion.

Validation

• Red before the fix: the focused regular-presentation XCTest selected one test and failed three assertions for a covered button, labeled image, and disabled button.
• Green: iOS XCTest build succeeded; focused runner tests 2/2, snapshot/presentation tests 18/18, private-AX tests 5/5; daemon occlusion/state/response/find Vitest files passed with 97 tests; xctest selection passed.
• Live on existing booted iPhone 17 Pro F7D6F9A4-4FCC-4DD7-AC0B-3280C9319CB9: regular and raw direct payloads both reported automation-press as hittable true with no interactionBlocked, snapshotQuality.backend tree, and XCTest backend diagnostics present (4/5). The changed lifecycle route passed its regular/raw app-switcher assertions and screenshot evidence. All scoped sessions were closed and isolated daemons cleaned.
• Final pnpm check:affected --run passed all runnable checks; native/device and coverage lanes remain GitHub-authoritative. The broad lifecycle run later reached the existing simulator observability check and stopped because CPU sampling is unavailable on simulators; that unrelated failure was not pursued.