fix(ypp): refresh 403'd on every real call — drop the auditDetails part (needs a partner scope)

Creator: 'when I attempt to refresh my YPP page, I get an error about not being
able to reach YouTube. Seriously?' Real log: channels.list failed (403) x3.

Root cause #1 (the 403): channels.list?mine=true&part=statistics,auditDetails,
contentDetails returns 403 insufficientPermissions when the token lacks the
youtubepartner-channel-audit scope — which the auditDetails part ALONE requires,
per the docs ('A request that retrieves the auditDetails part ... must provide an
authorization token that contains the youtubepartner-channel-audit scope'). That
scope is MCN partner tooling with a 2-week token-revocation rule; the app must not
hold it. TASK-39's 'current scopes suffice, no re-consent' slice-1 claim was wrong
for this part; mock-fake tests never touched the real API, so it shipped green and
403'd every refresh since 2026-09-22.
https://developers.google.com/youtube/v3/docs/channels/list

Fix: part=statistics,contentDetails only; standing flags removed from
ChannelStatsService -> YppStatSnapshot surface -> YppTrackerViewModel -> drawer,
replaced by an honest deep-link row ('Channel standing isn't exposed to YouTube
apps — check the Earn page'). YppSnapshot standing columns stay (schema-stable,
always false). channels.list failures now log the response BODY — the bare code
could not name insufficientPermissions, which is what made this undiagnosable.

Root cause #2 (found by the new Good Dog, masked by the 403): statistics come back
as JSON STRINGS ('350'); raw GetInt64() throws. Tolerant ReadInt64 (ValueKind-first;
JsonElement.TryGetInt64 THROWS on strings — type-in, not try-type).

Good Dog: ChannelStatsServiceTests.CaptureCurrent_RequestsNoAuditDetails_AndStillParsesTheSnapshot
(URL asserts no auditDetails + snapshot parses); YppPullOutTests fixture updated.
Recipes for both 403/scope and statistics-strings entered in MyMistakes.md.

Also shipped in the same commit (shared PreviewPane.xaml + ai.md): the audio-sync
status dot removal from the #77 feedback round (creator: 'what is the point of the
status light? Lose it') — IntToSyncBrushConverter deleted with it.

verify.sh gate: 0 warnings, 316/316 pass, scope-check clean.

TASKS.md

@@ -54,7 +54,7 @@
 | 36 | Gold pass | ☐ Queued (2026-09-01) | [`TASKS/task-36-gold-pass.md`](TASKS/task-36-gold-pass.md) |
 | 37 | Defaults vs current layout split | ☐ Queued (2026-09-20) | [`TASKS/task-37-defaults-current-split.md`](TASKS/task-37-defaults-current-split.md) |
 | 38 | Capture Window… backdrop (in-app window picker) | ✅ Done — shipped 2026-09-21 | [`TASKS/task-38-window-backdrop.md`](TASKS/task-38-window-backdrop.md) |
-| 39 | YPP journey tracker (slice 1: current-scope data) | 🔶 Slice 1 ✅ — 2026-09-22; slice 2 (Analytics + ETA) queued | [`TASKS/task-39-ypp-journey-tracker.md`](TASKS/task-39-ypp-journey-tracker.md) |
+| 39 | YPP journey tracker (slice 1: current-scope data) | 🔶 Slice 1 ✅ — 2026-09-22; **refresh 403 fixed 2026-09-23** (auditDetails part dropped); slice 2 (Analytics + ETA) queued | [`TASKS/task-39-ypp-journey-tracker.md`](TASKS/task-39-ypp-journey-tracker.md) |
 | 40 | App Settings round: active-camera picker + config dialog, gear move, defaults, accent | ☐ Queued (2026-09-22) — plan saved | [`TASKS/task-40-app-settings-round.md`](TASKS/task-40-app-settings-round.md) |
 | 41 | Test Stream mode: private test broadcast + TEST drawer (mock chat input + simulated events) | ✅ Done (2026-09-22) | [`TASKS/task-41-test-stream-mode.md`](TASKS/task-41-test-stream-mode.md) |
 | 42 | Top bar redesign: one REC-or-Stream surface, gear up top, sign-in/account zone world-gated | ✅ Done (2026-09-22) | [`TASKS/task-42-top-bar-redesign.md`](TASKS/task-42-top-bar-redesign.md) |