Initialize Android NTP app framework

project-docs/implementation/phase-plan.md

@@ -0,0 +1,86 @@
+# Phase Plan
+
+## NTP-P0 — Repository framework and delivery workflow
+
+Goal: initialize the project like the phase-gated Second Brain workflow.
+
+Deliverables:
+- Android Kotlin/Compose skeleton.
+- Room storage model draft.
+- Raw UDP NTP client draft.
+- Gitea Actions debug APK workflow.
+- Project docs, hard rules, and validation target.
+
+Gate:
+- `make validate-structure` passes.
+- Repo pushes to Gitea.
+
+## NTP-P1 — NTP probe correctness
+
+Goal: make the raw UDP NTP client reliable and testable.
+
+Deliverables:
+- Unit tests for packet timestamp parsing/encoding and warning mapping.
+- Probe result model with all required NTP fields.
+- Error handling for DNS failure, timeout, malformed packets, and unreachable hosts.
+
+Gate:
+- Unit tests pass.
+- Manual test against known public NTP servers succeeds.
+
+## NTP-P2 — Saved servers and dashboard MVP
+
+Goal: provide a useful saved server list and one-tap comparison dashboard.
+
+Deliverables:
+- Add/edit/delete servers.
+- Default server seed only on first run.
+- Latest result per server visible on dashboard.
+- Sort by latency, offset, stratum, reachability, health score.
+- Best candidate calculation.
+
+Gate:
+- Debug APK builds.
+- Manual emulator/device smoke test passes.
+
+## NTP-P3 — Continuous testing and disagreement detection
+
+Goal: support polling intervals and peer-group comparison.
+
+Deliverables:
+- Continuous mode at 1s, 5s, 10s, 30s.
+- Offset median and threshold outlier warnings.
+- Reference ID change warning.
+- Short history retention policy.
+
+Gate:
+- Continuous mode stops cleanly when disabled/backgrounded.
+- Battery/network behavior reviewed.
+
+## NTP-P4 — Profiles and export
+
+Goal: make the app practical for home/customer troubleshooting.
+
+Deliverables:
+- Profile CRUD and server assignment.
+- Export/share current results and history as text/CSV.
+- Import server list design for later CSV/YAML.
+
+Gate:
+- Export contains no hidden telemetry or private app metadata.
+- Profile switching works on device.
+
+## NTP-P5 — UX polish and release prep
+
+Goal: prepare signed release builds.
+
+Deliverables:
+- Dark/light mode polish.
+- Empty/error/loading states.
+- Signed release build workflow using Gitea secrets.
+- Release checklist.
+- Open Android Date & Time settings action if local clock offset warning is present.
+
+Gate:
+- Lint/tests/build pass.
+- Permission and privacy review passes.