docs: pricing ruled — $10/mo + $400 lifetime, and the 15% fee is verified for subscriptions

Reconcile the pending doc edits with the creator's actual ruling, and close the
revenue-share question that was blocking the monthly price.

Verified from the App Developer Agreement v8.10 PDF itself (downloaded and
text-extracted, not a search excerpt). Section 6(b) has only three tiers:
6(b)(i) 15% for Apps and their In-App Products *not listed in* 6(b)(iii);
6(b)(ii) 12% Games-only; 6(b)(iii) 30% for Xbox console apps/games, Xbox
non-subscription IAP, and Windows 8/Phone 8. LlamaCasty is a Windows PC App,
so 6(b)(i) governs BOTH tiers -- there is no subscription surcharge. The
agreement's own changelog (v8.0, Oct 26 2017) states it outright: "implement
the 85/15 revenue share for non-Game subscriptions."

  => $10/mo nets $8.50 (~$102/yr); $400 lifetime nets $340.

Also confirmed: the 15% applies after VAT/GST (Net Receipts definition),
payouts are monthly above a $50 threshold, and no better small-indie rate
exists in the standard terms.

Creator ruling recorded: $10/mo subscription or $400 lifetime, no annual, no
.99. This supersedes the 2026-09-21 one-time $29 -> $49 model.

Two obligations ADA 6(h) attaches to the recurring tier, recorded because they
change its risk profile and are the reason lifetime is the hedge: we must
fulfil the subscription for the entire period as marketed (on breach Microsoft
may refund the full amount plus taxes in its sole discretion), and raising the
price disables auto-renew -- so $10 is effectively locked for the product's life.

Stale facts fixed in the same change rather than appended:
- research-store-certification.md: IARC was 11.11.1/11.11.2 in one table and
  10.11.1 in another; corrected to 10.11.x.
- research-store-certification.md: policy 10.8.1/10.8.2 still asserted "Polar
  explicitly permitted" and "tick the third-party purchase box". Void now that
  Store IAP is the route and Polar is being torn down.
- task-48: the working YouTube demo account (10.3.1) was accidentally dropped
  from the certification list during the Store-IAP edit. Restored -- a reviewer
  cannot use the app without one.
- MyMistakes.md: the verified-fact-vs-decided-outcome lesson now closes its
  loop (the creator did rule the way the research pointed), and records the
  over-correction that followed.

Docs-only. No code, no build, no tests.

TASKS/task-48-distribution-msix.md

@@ -55,16 +55,24 @@ ONLY paid delta (TASK 36 item 2). Store IAP changes how the bit is *obtained*, n
 
 ### Still to verify (does not block packaging work)
 
-- ☐ **Current Store revenue-share terms.** ⚠️ **Do not assume any percentage** — the terms have
-  moved more than once and smaller indie apps sometimes qualify for better rates. **Verify
-  before setting a price.** Microsoft also requires that any IAP products and their pricing be
-  declared in Partner Center.
-- ☐ **Store IAP tier shape** — ⛔ **no annual tier, and that is now a settled constraint, not
-  a preference:** Microsoft does not pro-rate, and *"monthly subscriptions and initial
-  (pre-renewal) purchases aren't eligible for a prorated refund"*, so a first-year annual
-  subscriber who cancels loses the remaining months in most countries **and the developer
-  cannot refund it**. Declare a **monthly subscription**; a **lifetime** product (~$300, clean
-  number, no `.99`) is the open question and the natural hedge. ⛔ **No `.99` prices.**
+- ☑ **Current Store revenue-share terms — VERIFIED 15%, subscriptions included.** Read from the
+  ADA v8.10 PDF (downloaded and text-extracted), §6(b): 15% for Apps and their In-App Products
+  *not listed in* 6(b)(iii); 12% is Games-only; 30% is Xbox console / Xbox non-subscription IAP /
+  Windows 8. LlamaCasty is a Windows PC App, so **6(b)(i) 15% governs** ⇒ `$8.50/mo` net,
+  `$340` lifetime net. The agreement's own changelog (v8.0, Oct 26 2017) states it plainly:
+  *"implement the 85/15 revenue share for non-Game subscriptions."* Smaller-indie better rates
+  were **not** found in the standard terms. Microsoft also requires that any IAP products and
+  their pricing be declared in Partner Center.
+- ☑ **Store IAP tier shape — ✅ DECIDED 2026-09-27: `$10/mo` subscription + `$400` lifetime,
+  no annual.** Declare **two** products in Partner Center: one auto-renewing monthly
+  subscription, one non-expiring lifetime IAP. ⛔ **No `.99` prices** (settled). ⛔ **No annual
+  product** — Microsoft does not pro-rate: *"monthly subscriptions and initial (pre-renewal)
+  purchases aren't eligible for a prorated refund"*, so an annual sub cancelled in year 1
+  forfeits the remainder **and the developer cannot refund it**. Net after the 15% Store Fee
+  (verified, §6(b)(i) — applies to non-Game subscriptions too): **`$8.50/mo` and `$340`**.
+  Note ADA §6(h): we must fulfil the subscription for the whole period, and **raising the price
+  disables auto-renew** — so `$10` is effectively locked for the product's life. ⛔ A discounted
+  subscriber→lifetime upgrade SKU is **not** approved; do not declare one.
 - ☐ Individual vs Company Partner Center account (10.8.3 / 10.14 — see
   `research-store-certification.md` §11 item 1). **Get this right before enrolling**; a
   Store+IAP product needing financial info for primary functionality would require Company,
@@ -139,6 +147,10 @@ relevant check: the app must start promptly, stay responsive, and shut down grac
 **In Partner Center (submission):**
 
 - ☐ **The IARC age-rating questionnaire** (10.11.1) — general audience, 12+ territory
+- ☐ **A working YouTube demo account** (10.3.1) — the app is useless to a reviewer without one.
+  Must be a real, maintained account able to sign in and start a stream; a dead or
+  credentials-lapsed account is a rejection. ⛔ **This was accidentally dropped from this list**
+  during the Store-IAP edit — it is in `research-store-certification.md` §4 and must be done.
 - ☐ **Declare the IAP products and their pricing** in Partner Center (required for Store IAP).
   ⛔ **No `.99` prices** — creator ruling, and incoherent for a no-dark-patterns brand. Confirm
   the **net** after the revenue share, not the list.