feat(ypp): the three eligibility bars, with dated thresholds (TASK 39·2)

YouTube moves the goalposts, so the app stops modelling them as its own truth and shows progress against
a threshold table that carries the date it was read.

- `Models/YppProgress.cs` — pure: three metrics, per-criterion met, and `MeetsPublishedRule`, which
  encodes the real shape of the rule (subscribers AND either view route). The drawer says "x of 3 criteria
  met — YouTube reviews eligibility" and spells out the either/or, so "2 of 3" can't be misread.
- `Services/YouTubeAnalyticsService.cs` — the two numbers only Analytics publishes: long-form watch hours
  (trailing 12 months, `creatorContentType==video`) and Shorts-feed views (90 days, `==shorts`). No rows
  means NO DATA, not zero.
- **Thresholds are data with a publication date** (`YppThresholds.AsOfUtc`, shown in the drawer) and a
  test fails once that reading is more than 180 days old. The 2027-02-01 doubling (4,000h → 8,000h,
  10M → 20M Shorts views) resolves from the date, not from an edit.
- **No Analytics scope → no invented numbers:** the drawer explains the missing consent instead of drawing
  two empty bars as zero. Money stays behind 3·20's "Show monetary metrics" toggle.
- Fan-funding tier (500 subs) demoted to a single muted line, since the three bars are the ad-revenue path.

Tests: `YppProgressTests` — either/or eligibility, subscribers alone insufficient, Shorts as a qualifying
route, bars clamp at 100%, the doubling date, the staleness guard, Analytics parsing (no rows = no data),
and compact value formatting. FAST gate: 567 passed, 0 failed, 0 warnings.

Models/YppThresholds.cs

@@ -13,6 +13,10 @@ public static class YppThresholds
     /// <summary>The date the Tier-2 ad-revenue bars double for new applicants.</summary>
     public static readonly DateTime Tier2DoublingDate = new(2027, 2, 1);
 
+    /// <summary>When these thresholds were last read from YouTube's published requirements. Shown in the
+    /// drawer and asserted by a test, because YouTube moves the bar and a stale bar must not look current.</summary>
+    public static readonly DateTime AsOfUtc = new(2026, 11, 5);
+
     /// <summary>Fan-funding tier (before the full ad/YouTube Premium revenue tier).</summary>
     public static TierThreshold Tier1 { get; } = new("Fan funding", 500, 3_000, 3_000_000);