[FARMSLOT DEMO - DO NOT MERGE] Playground: show debug banner after sample audio loads

[abretonc7s]

Description

Change Requested

On the Audio Playground Import screen, show a red debug banner after the sample audio file has been loaded.

Banner text must be exactly:

FARMSLOT DEMO: SAMPLE AUDIO LOADED

The banner should appear above the waveform / audio preview area.

Requirements

• Show the banner only after sample audio has been loaded.
• Do not show the banner before any audio is loaded.
• Background color: red.
• Text color: white.
• Keep styling minimal.
• This is a debug-only POC and must not be merged.

Acceptance Criteria

• Given the Import screen has no loaded audio, the banner is not shown.
• Given the user taps Load Sample and the sample audio loads successfully, the red banner is shown.
• The banner text is exactly FARMSLOT DEMO: SAMPLE AUDIO LOADED.
• The implementation is minimal and easy to revert.
• The branch or PR is clearly marked DO NOT MERGE.
• Validation proves the behavior on:
  • iOS
  • Web
  • Android

Validation Requirements

The agent must create or update a Farmslot recipe that:

1. Opens the Import screen.
2. Asserts the banner is absent before loading sample audio.
3. Taps load-sample-button.
4. Waits for sample audio / preview readiness.
5. Asserts the banner is present with exact text.
6. Captures screenshot evidence.
7. Runs with matrix validation:

bash scripts/agentic/validate-recipe.sh "$TASK_ARTIFACT_DIR/recipe.json" \
  --matrix ios,android,web \
  --artifacts-dir "$TASK_ARTIFACT_DIR/recipe-runs/final"

Demo Notes

This issue exists only to demonstrate Farmslot dispatch, agent implementation, cross-platform recipe validation, evidence artifacts, and PR review flow.