build(#83): widget triple → generated Java shims (AppWidgetProvider + actions + configure)

[hyperpolymath]

Sub-task of #83 (gossamer migration).

Replace the home-screen widget triple with generated Java shims → JNI into Rust:

• NeurophoneAppWidget.kt → AppWidgetProvider shim
• NeurophoneWidgetActions.kt → BroadcastReceiver shim
• NeurophoneWidgetConfigureActivity.kt → Activity shim

Owner open question: is it acceptable to drop the configure activity (RFC #96 listed it as droppable)? Parallelizable after the gossamer Android scaffolding.

[hyperpolymath]

Owner decision: approved to drop NeurophoneWidgetConfigureActivity — no configure-Activity shim needed. The widget triple reduces to AppWidgetProvider + actions BroadcastReceiver (both as gossamer-hosted/generated shims → JNI into Rust/Spark).

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Generated by Claude Code