Gate C: phone landscape + tablet layout/orientation audit

[CodeSculptor]

Tracking the Gate C work from RELEASE_PROCESS.md: the phone-portrait layout is the primary target and is verified, but other orientations are unverified and may leak TV/leanback layout assumptions.

To audit (from the release checklist):

• Phone landscape
• Small tablet portrait
• Small tablet landscape
• Large tablet portrait
• Large tablet landscape
• No landscape-only controls appear in portrait without adaptation
• Important controls reachable by touch; important text readable

These rows are currently Unknown in FEATURE_MATRIX.md and must be resolved before a 1.0. Files this as the missing tracking issue for that KNOWN_ISSUES entry.