Import december-2020-12-18 from private repo (scrubbed 2026-05-27)

Targets Rec Room 2020.12.18 client.

Re-import after adding:
- DorkNet.ClientMod/dorknet-clientmod.json.template — config schema
  the launcher's manifest-driven patcher renders into UserData/.
- tools/build-patcher-zip.ps1 — produces the dorknet-clientpatch-{key}.zip
  Release asset the launcher fetches.
- .github/workflows/release.yml — auto-publishes both Release assets
  on v1-december-* tag push.

Scrubbed via maintainer-side scrub-for-public.ps1: same drop rules as
the prior import, plus build-patcher-zip.ps1 added to the tools/
allow-list so it survives the scrub.

DorkNet.Server/Data/MIGRATIONS.md

@@ -0,0 +1,135 @@
+# Migrations & legacy data upgrades
+
+## Current state (2026-05-25 — post-consolidation)
+
+- **One migration** under `Migrations/`: `20260525181055_Initial.cs`
+  (generated by `dotnet ef migrations add Initial` against the
+  current entity model — captures all 67 `DbSet<>` tables).
+- **`LegacyUpgrades.cs`** holds idempotent data transforms that can't
+  be derived from the entity model. Runs once per server boot, after
+  EF migrations complete and before `RoomService.SeedAsync()`.
+
+## What changed in the consolidation
+
+Before this pass, the codebase had two parallel schema-management
+mechanisms accumulating per-feature noise:
+
+1. **34 EF migrations** under `Migrations/` — applied to SQLite via
+   `db.Database.Migrate()`.
+2. **65 `RunPatchAsync` calls** in `Program.cs:574-1011` — idempotent
+   Postgres `ALTER`/`CREATE` statements layered on top of
+   `EnsureCreated()`, because the Postgres path skipped EF migrations.
+
+Both were collapsed in 2026-05-25:
+
+- The 34 migrations were deleted and regenerated as a single
+  `20260525181055_Initial`. The model snapshot was regenerated to match.
+- The `RunPatchAsync` block was deleted entirely. Postgres still uses
+  `EnsureCreated` (which now reads the same up-to-date entity model);
+  no per-feature patches needed.
+- The PhotonRegion coerce (the only data transform in the block)
+  was moved into `LegacyUpgrades.CoercePhotonRegionAsync`.
+- The Storage admin page (`admin-ui/src/pages/Storage.tsx`) and
+  `StorageBackfillController.cs` were deleted — they were the UI for
+  draining the legacy `RoomDataBlobs.Bytes` column into S3, which is
+  no longer needed.
+
+## Production cutover (one-time SQL)
+
+Existing prod databases need a one-time fixup to tell EF "the new
+Initial is already applied here" so the next boot doesn't try to
+`CREATE TABLE` over existing data.
+
+### Postgres path
+
+The Postgres production schema was built via `EnsureCreated()` plus
+the (now-deleted) `RunPatchAsync` block. **No `__EFMigrationsHistory`
+table exists** because EF Core only creates it when `Migrate()` runs.
+Postgres continues to use `EnsureCreated()` post-consolidation, so
+there's *nothing to do* — `EnsureCreated()` reads the entity model,
+sees the schema already matches, and no-ops. Just deploy the new
+build.
+
+If you ever switch the Postgres path to `Migrate()`, run this once
+before the cutover deploy:
+
+```sql
+CREATE TABLE IF NOT EXISTS "__EFMigrationsHistory" (
+    "MigrationId" character varying(150) NOT NULL,
+    "ProductVersion" character varying(32) NOT NULL,
+    CONSTRAINT "PK___EFMigrationsHistory" PRIMARY KEY ("MigrationId")
+);
+
+INSERT INTO "__EFMigrationsHistory" ("MigrationId", "ProductVersion")
+VALUES ('20260525181055_Initial', '10.0.0');
+```
+
+### SQLite path (dev DBs)
+
+Handled automatically by `BaselineExistingSchemaIfNeeded()` in
+`Program.cs`. On boot it detects two cutover scenarios and reconciles
+the migration-history table to match the assembly's current migration
+list:
+
+- **Legacy EnsureCreated** — schema present, history table absent.
+  Creates the history table and stamps the Initial.
+- **Stale history post-consolidation** — schema present, history has
+  entries from the old 34 per-feature migrations. Wipes them and
+  stamps the Initial.
+
+`Migrate()` then sees the reconciled history and no-ops. **No manual
+SQL needed.**
+
+#### Gotcha: partial-migration dev DBs
+
+`BaselineExistingSchemaIfNeeded` assumes the on-disk schema matches
+the current entity model. If a dev DB was created mid-cycle and
+missed some of the later migrations (e.g. `AddPlaylists`,
+`AddClubAnnouncementsAndCategories`, `AddWeeklyChallengeSettings`),
+the reconciled boot will succeed but the missing tables will cause
+queries to fail at runtime (`no such table: Playlists`).
+
+Fix: either delete the dev DB and re-seed, or apply the missing
+migrations against your DB *before* upgrading to the consolidated
+build. The latter requires checking out the pre-consolidation commit,
+running `dotnet ef database update`, then checking back out.
+
+## Adding migrations after consolidation
+
+> One release = one migration. Don't accumulate per-feature micros.
+
+The post-consolidation discipline:
+
+1. **Iterate freely** between releases — edit entities, run the server
+   against your dev DB (sqlite under `bin/Debug/.../data/`). EF will
+   reject the schema mismatch and you fix it locally however you like.
+   Local DBs are disposable.
+2. **At release cut**, run `dotnet ef migrations add Release_v{N}_{M}`
+   once to bundle all the schema deltas from the iteration window into
+   a single migration.
+3. **Data transforms** (renames of seed rows, backfills, etc.) go in
+   `LegacyUpgrades.cs` as new private methods, NOT as new migrations.
+   They run on every boot and are idempotent.
+
+## Regenerating Initial from scratch
+
+If the model drifts far enough that you want to re-collapse to one
+Initial again:
+
+```pwsh
+# 1. Delete all migration files + the model snapshot.
+Remove-Item DorkNet.Server\Migrations\2026*.cs
+Remove-Item DorkNet.Server\Migrations\DorkNetDbContextModelSnapshot.cs
+
+# 2. Regenerate Initial from the current entity model.
+dotnet ef migrations add Initial `
+    --project DorkNet.Server `
+    --context DorkNetDbContext
+
+# 3. Eyeball the generated Up() body before committing — verify it
+#    captures every DbSet<> in DorkNetDbContext plus every
+#    relationship and index.
+```
+
+Existing DBs auto-reconcile via `BaselineExistingSchemaIfNeeded`
+(SQLite) or no-op via `EnsureCreated` (Postgres). No manual cutover.