feat: add product-aware deletion emails and subdomain deletion/downloads routes

- Extend DeletionForm with product discriminator and configurable cooldown cookie
- Extract env-free deletion email helpers into deletion-email.ts with Lineage/Nessa branding
- Make misc.sendDeletionRequestEmail mutation product-aware (subject, html content, cookie)
- Replace legacy /deletion/life-and-lineage page with 308 redirect to lineage subdomain
- Add Lineage and Nessa subdomain deletion route modules with shared content components
- Add Lineage downloads route modules with shared content
- Update privacy policy deletion link to lineage subdomain

src/routes/lineage/deletion-content.ts

@@ -0,0 +1,71 @@
+/**
+ * Pure content + metadata for the Lineage per-subdomain account-deletion page
+ * (task 11).
+ *
+ * Imports NOTHING from solid-js / @solidjs/router / @solidjs/meta so the
+ * constants here can be unit-tested in `bun:test` without spinning up the
+ * router / MetaProvider, mirroring the `landing-content.ts` /
+ * `downloads-content.ts` pattern.
+ *
+ * Cross-task contracts encoded here:
+ *  - `DELETION_PRODUCT_KEY` is the `product` discriminator passed to the
+ *    generalized `misc.sendDeletionRequestEmail` mutation
+ *    (`src/server/api/routers/misc.ts`) so the email copy + cooldown cookie
+ *    are Lineage-branded. The legacy mutation default is also `"lineage"`,
+ *    so the migrated page is backward-compatible with any in-flight cooldown.
+ *  - `DELETION_COOKIE_NAME` is the cooldown cookie read/written by
+ *    `DeletionForm` — kept as the original `deletionRequestSent` name so
+ *    installed cooldown state from the legacy `/deletion/life-and-lineage`
+ *    route is honored across the 308 redirect (no forced re-send).
+ *  - `DELETION_GRACE_PERIOD_MS` mirrors `LINEAGE_CONFIG.DELETION_GRACE_PERIOD_MS`
+ *    (24h) — the window during which a user may email michael@freno.me to
+ *    cancel the deletion before the central account row + per-user Turso DB
+ *    are dropped. Surfaced here as a pure constant so the page copy + tests
+ *    can assert the grace window without importing the server-side config
+ *    module (which validates ~30 secrets at import time).
+ *  - `LEGACY_DELETION_REDIRECT_TARGET` is the canonical absolute URL the
+ *    legacy `/deletion/life-and-lineage` route 308-redirects to.
+ */
+import type { PageHeadProps } from "~/components/page-head-meta";
+
+/**
+ * Product discriminator for the generalized `sendDeletionRequestEmail`
+ * mutation. The Lineage flow is the original / default product.
+ */
+export const DELETION_PRODUCT_KEY = "lineage" as const;
+
+/**
+ * Cooldown cookie name for the Lineage deletion request.
+ *
+ * Kept identical to the legacy cookie so an in-flight cooldown survives the
+ * `/deletion/life-and-lineage` → `lineage.freno.me/deletion` redirect.
+ */
+export const DELETION_COOKIE_NAME = "deletionRequestSent";
+
+/**
+ * Grace period (ms) during which a Lineage account deletion can be cancelled
+ * by emailing michael@freno.me. Mirrors
+ * `LINEAGE_CONFIG.DELETION_GRACE_PERIOD_MS` (24h).
+ */
+export const DELETION_GRACE_PERIOD_MS = 24 * 60 * 60 * 1000;
+
+/**
+ * Human-readable grace-window copy interpolated into the deletion page body.
+ */
+export const DELETION_GRACE_PERIOD_LABEL = "24-hour";
+
+/** Base page title (site suffix appended by PageHead). */
+export const PAGE_META: PageHeadProps = {
+  title: "Account Deletion",
+  description:
+    "Request account deletion for Life and Lineage. All account data and remote saves are removed after a 24-hour grace period."
+};
+
+/**
+ * Canonical absolute URL the legacy `/deletion/life-and-lineage` route
+ * 308-redirects to (task 11). Kept here so tests can assert the redirect
+ * target without importing the route module (which would pull the server
+ * runtime).
+ */
+export const LEGACY_DELETION_REDIRECT_TARGET =
+  "https://lineage.freno.me/deletion";