docs(distribution): Steam is the only channel — the zip, winget and the Store are dead

The site said "Coming soon to Steam" while the app docs still said direct download plus
winget primary with Steam parked. One of them had to move, and the creator's ruling is
Steam exclusive: a free app on Steam with the paid edition as a Steam DLC, and the
$10/month plan sold off-Steam by Polar.

Records the constraint that shapes the code, not just the prose:
- Steamworks requires in-app purchases to use the Steam Wallet (Microtransactions doc,
  quoted in commercial.md), so the monthly is *stated*, never *sold*, inside a Steam
  build; the lifetime is plain DLC bought on the store page and read with BIsDlcInstalled.
- Entitlement is `steamDlcOwned || polarKeyValid`, both resolving to one OutputProfile.
  steam_api64.dll ships beside the exe and is a functional dependency, not the rejected
  "IP protection" native DLL — without it DLC ownership cannot be read. Launched without
  Steam, the app falls back to the free profile rather than refusing to start.
- Signing is moot: Steam installs never meet SmartScreen. Artifact Signing stays on the
  shelf for the day a non-Steam download exists. Year-one fixed cost is ~$115.
- The exe rename must land before the first depot upload — Steamworks warns about
  renaming a live exe.

Distribution.md is rewritten to SteamPipe mechanics (publish output, depot, steamcmd,
DLC wiring, clean-account purchase/refund test). product.md, decisions.md (a new
"Steam exclusive" entry with every dead vector), TASKS.md (Steamworks entitlement row,
Steam packaging row), ai.md, index.md and the TASK 48 banner follow. MyMistakes.md gains
the Steam rules that cost real time today: installs skip SmartScreen, updates are free,
the Wallet rule, and the recurring-billing caveat.

TASKS.md

@@ -10,13 +10,15 @@
 **The surge week (4 days, in this order).** Not every row below — this slice only, because it is
 what the first public release is waiting on:
 
-1. **Artifact shape** — `LlamaCasty.exe` rename (three pack URIs), `scripts/publish.sh`,
-   portable mode. Ends with a zip that runs on a clean machine.
+1. **Artifact shape** — `LlamaCasty.exe` rename (three pack URIs), `dotnet publish` profile with
+   `steam_api64.dll` beside the exe. Ends with a build that starts standalone and falls back to the
+   free profile.
 2. **OutputProfile gate** — ≤921,600 px / ≤30 fps for the stream **and** the recorder, greyed tier
    entries, plus the TASK 53 geometry tests that pin every tier.
-3. **Entitlement seam** — `IEntitlement` against Polar's customer-portal API with a fake for tests,
-   `--activate` parsing, system messages.
-4. **Real-machine day** — licence UI skeleton, a clean-profile install, a test broadcast.
+3. **Entitlement seam** — `IEntitlement` with the Steam DLC path and a fake for tests, Polar's
+   customer-portal path for the monthly, `--activate` parsing, system messages.
+4. **Real-machine day** — licence UI skeleton, a Steam-less launch proving the free profile, a test
+   broadcast.
 
 Detail: [`commercial.md`](docs/ai/commercial.md) → Output profile / Entitlement;
 [`Distribution.md`](Distribution.md). Day 5, if the four go well: the visibility picker (a hard
@@ -49,11 +51,12 @@ Dog test.
 | 50 | ☐ | One-button publish of the local recording (resumable upload) | [`task-50`](TASKS/task-50-publish-recording.md) |
 | 53 | ☐ | Output-format contract: pin every tier with a geometry test, prove 9:16 end-to-end, recorded file matches output | [`task-53`](TASKS/task-53-output-formats.md) |
 | 54 | 🔶 | Freemium: EULA + privacy shipped; **no licence path built** — needs the entitlement seam, the output-profile cap and the licence UI below; site copy still says free forever | [`task-54`](TASKS/task-54-marcom-free-merch.md) |
-| — | ☐ | **Entitlement seam** — `IEntitlement` over Polar's customer-portal API (org ID public, org token never in the app), `conditions: {channel_id}`, 2 activations, 7–14 day lease, `--activate` CLI. **No claim page, no server** | [`commercial`](docs/ai/commercial.md) |
+| — | ☐ | **Steamworks entitlement** — `steam_api64.dll` + `SteamAPI.Init`, `BIsDlcInstalled(dlcAppId)` behind `IEntitlement`, free profile when Steam is absent | [`commercial`](docs/ai/commercial.md) |
+| — | ☐ | **Entitlement seam** — Polar customer-portal path for the monthly (org ID public, org token never in the app), `conditions: {channel_id}`, 7–14 day lease, `--activate` CLI. **No claim page, no server** | [`commercial`](docs/ai/commercial.md) |
 | — | ☐ | **OutputProfile gate** — ≤921,600 px / ≤30 fps for stream **and** recording, greyed tier entries, live re-resolve, never mid-stream | [`commercial`](docs/ai/commercial.md) |
-| — | ☐ | **Licence UI** — key entry + four states, 7/1/0-day notices, portal link, licence ID in About | [`commercial`](docs/ai/commercial.md) |
+| — | ☐ | **Licence UI** — four states, 7/1/0-day notices, "monthly is on the website, not Steam" line, portal link, licence ID in About | [`commercial`](docs/ai/commercial.md) |
 | — | ☐ | **System messages** — `SystemMessage` + `MessageCenter`, strip above the dock, dedupe by key, short history, never composited | [`ui-surface`](docs/ai/ui-surface.md) |
-| — | ☐ | **Packaging** — rename, `scripts/publish.sh`, portable mode; then `llamacasty-releases` repo + Gitea→GitHub push mirror, `gh release create`, winget manifest. Signing **deferred** until two subscribers | [`Distribution.md`](Distribution.md) |
+| — | ☐ | **Steam packaging** — rename, `publish` output + `steam_api64.dll`, depot, `steamcmd` upload, store page + assets, DLC app | [`Distribution.md`](Distribution.md) |
 | — | ☐ | **Training-video series** — capture the first 8–10 recurring questions as videos on `@llamacasty`; each is documentation, channel content and monetization at once | MARCOM → support→content loop |
 | 9·5 | ☐ | Webcam identity key reconciliation | [`task-09`](TASKS/task-09-live-stream-management.md) |
 | 14 | 🔶 | Creator feedback batch — branch 3+ | [`task-14`](TASKS/task-14-creator-feedback-batch.md) |