test(guide): require semantic catch-up selection

[MrFr3di]

Refs #305, parent #184.

Historical RED evidence for Task 5 only. Exact head bd1d0cc3ea1c026f9cc0d9c4fe5903aafd70a00d adds tests requiring:

• viewport clipping to preserve original EPG programme start/end separately from visible geometry;
• status/current programme -> Live, completed programme -> CatchupProgram(original bounds), future programme -> no launch;
• bounded deterministic channel-scoped opaque programme identity with no raw channel/EPG/title leakage.

Production Guide playback selection is intentionally absent on this branch. Expected RED is unresolved original-bound projection fields and GuidePlaybackSelection / guidePlaybackSelection. Keep draft and do not merge.