feat(achievements): wall sync drain worker + review fixes (epic PR3) (#592)

* feat(achievements): wall sync drain worker (epic PR3, client side)

Background dead-letter worker that POSTs queued Feat unlocks/removals to the
hosted feedback-achievements wall. Idle unless FEEDBACK_ACHIEVEMENTS_WALL_URL
is set; uses requests + the client-token header (mirrors lyrics_transcribe).

Dead-letter, never drop (pure engine.drain_decision):
  network err / 429 / 5xx -> keep pending (retry)
  other 4xx               -> dead_letter (diagnosable, replayable)
  2xx                     -> delete on server ack
remove-me enqueues a wall removal keyed by the reused player_hash.

Verified by an end-to-end staging round-trip (earn a Feat -> drains onto the
wall with name + short hash -> remove-me -> wall empties) with no IP in tables
or access logs. 42 plugin tests pass (test_sync.py adds the decision table +
ack/retry/dead-letter retention + four-field on-the-wire payload).

The hosted service lives in the new feedback-achievements repo.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* fix(achievements): address local review findings (epic)

Bugs caught in the pre-merge review loop:

- secret_witching Feat was DEAD: post_activity wrote witching_nights_run to the
  DB before snapshotting prev_tiers, so diff_unlocks never saw the fresh unlock.
  Fold the run into the activity delta instead (same asymmetry chart_encore
  uses) so the 7th-night unlock is detected. +regression tests.
- chart_encore broke across restarts: per-chart counter keyed on abs(hash(str)),
  which Python salts per-process (PYTHONHASHSEED). Use a stable sha1 digest so
  the same chart accumulates across sessions. +regression test.
- Bounded the per-activity counter read: _read_counters no longer pulls the
  unbounded chart_plays:* rows (they're bumped/read individually).
- screen.js: gate note:hit/miss on an active-song flag so tuner/calibration note
  events can't inflate Feats or flush a phantom chart:null session.
- screen.js: P-III — prefix the plugin localStorage key (achievements:profile-cat).
- screen.js: extract the duplicated local-ISO-date helper.

45 plugin tests pass (3 new). Wall-side review fixes are in the
feedback-achievements repo.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* feat(achievements): default the drain worker to the hosted wall

Point FEEDBACK_ACHIEVEMENTS_WALL_URL's default at the live got-feedback wall
(https://feedback-achievements.onrender.com) so the drain worker targets it out
of the box; still env-overridable for self-hosting/staging. Nothing publishes
unless the user opted in AND has a profile identity, so a default URL alone
sends nothing.

Tests disable the default (autouse fixture) so no test ever POSTs to production;
drain logic is covered via _drain_once() with an injected poster. 45 pass.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plugins/achievements/screen.js

@@ -33,7 +33,7 @@
     var registered = {};   // id -> def (contributed + expanded baseline defs)
     var earned = {};       // id -> { tier, cls, category }
     var baseline = null;   // /catalog baseline blob
-    var CAT_KEY = 'v3-profile-ach-cat';
+    var CAT_KEY = 'achievements:profile-cat';  // P-III: plugin localStorage keys prefixed with plugin id
     var INSTRUMENTS = ['guitar', 'bass', 'drums', 'keys'];
 
     function progState() {
@@ -172,11 +172,17 @@
         postUnlock(def, tier).then(function () { refreshEarned().then(scheduleRender); });
     }
 
+    // Local calendar date 'YYYY-MM-DD' (one source of truth for both the
+    // steady-hands day ledger and the witching-night date below).
+    function localISODate(d) {
+        d = d || new Date();
+        return d.getFullYear() + '-' + String(d.getMonth() + 1).padStart(2, '0') + '-' + String(d.getDate()).padStart(2, '0');
+    }
+
     // growth-streak + challenger record on real competency events (date ledger /
     // distinct challenge sets) — kept as bookkeeping over EVENTS, never activity.
     function recordGrowthDay() {
-        var date = new Date();
-        var iso = date.getFullYear() + '-' + String(date.getMonth() + 1).padStart(2, '0') + '-' + String(date.getDate()).padStart(2, '0');
+        var iso = localISODate();
         fetchJSON('/report-criterion', {
             method: 'POST', headers: { 'Content-Type': 'application/json' },
             body: JSON.stringify({ criterion_id: 'steady_hands_days', token: iso }),
@@ -190,17 +196,21 @@
 
     // ── Activity (Feats): in-memory session counters, flushed on song:ended ───
     var session = { notesTotal: 0 };           // cumulative across this sitting
-    var song = { hits: 0, streak: 0, maxStreak: 0, chart: null };
-    function resetSong(chart) { song = { hits: 0, streak: 0, maxStreak: 0, chart: chart || null }; }
+    // `active` gates note counting to an actual song in progress — without it,
+    // note:hit/miss from the tuner or input-calibration would inflate Feats from
+    // non-song input and flush a phantom streak with chart:null.
+    var song = { hits: 0, streak: 0, maxStreak: 0, chart: null, active: false };
+    function resetSong(chart) { song = { hits: 0, streak: 0, maxStreak: 0, chart: chart || null, active: true }; }
 
     function flushActivity(seconds) {
+        if (!song.active) return;   // no active song → nothing to flush (ignore stray events)
+        song.active = false;
         // No notedetect → song.hits stays 0; notes-based Feats simply don't move
         // (graceful degradation). song_done / seconds / chart still flow so the
         // notedetect-free Feats (Road Warrior, Time Served, Encore) progress.
         var hour = new Date().getHours();
         var isNight = hour >= 2 && hour < 5;
-        var d = new Date();
-        var iso = d.getFullYear() + '-' + String(d.getMonth() + 1).padStart(2, '0') + '-' + String(d.getDate()).padStart(2, '0');
+        var iso = localISODate();
         var body = {
             notes: song.hits,
             session_notes: session.notesTotal,
@@ -364,13 +374,17 @@
             resetSong(e && e.detail && e.detail.filename);
         });
         bus.on && bus.on('note:hit', function () {
+            if (!song.active) return;   // ignore tuner/calibration note events
             song.hits++; song.streak++; session.notesTotal++;
             if (song.streak > song.maxStreak) song.maxStreak = song.streak;
         });
-        bus.on && bus.on('note:miss', function () { song.streak = 0; });
+        bus.on && bus.on('note:miss', function () { if (song.active) song.streak = 0; });
         bus.on && bus.on('song:ended', function (e) {
             flushActivity(e && e.detail && (e.detail.time || e.detail.audioT));
         });
+        // Song stopped/abandoned without a natural end → mark inactive so stray
+        // note events after it don't accrue against a phantom (chart:null) song.
+        bus.on && bus.on('song:stop', function () { song.active = false; });
     }
 
     if (document.readyState === 'loading') {