feat: file blocks (#10)

Phase 3, part 2 (`docs/design.md`, "Next"): file blocks. Moderators block a file network-wide by its sha256, so a removed product can't come back under another name or catalog.

**Blocking**
- A file's page (Console → Blocks → a file) shows whether it's blocked and the products using it, so a moderator sees what a block removes before confirming ("Block and remove 2 products").
- Moderators reach it from a product's files (each has a Block link for them) or by pasting a sha256 into the Blocks tab, which also lists blocked files.
- Blocking a file:
  - removes every product with a revision using it. Each removal is audited as `product.remove` with the file, so creators are notified and can appeal it as before.
  - puts a `{type: "block", sha256}` change in the changes feed of every catalog hosting it, meaning: delete it whatever uses it. (t5de-catalog doesn't read the feed yet.)
  - refuses uploads with it from then on (409 `blocked`). Each attempt is audited as `file.blocked_upload` with the person and catalog, so moderators see who tried.
- Unblocking lets the file in again. The products it removed stay removed until a moderator restores them, one by one.
- Who: `product:remove` hub-wide (moderators and admins). The Blocks tab shows only for them.

**API**: `GET /api/v1/blocks`, and `GET`/`PUT`/`DELETE /api/v1/blocks/:sha256` (`docs/products.md`).

**Migration** `0013_file_blocks`: the `file_block` table, and a GIN index on revisions' file lists, so finding the products using a file doesn't scan every revision.

**Checks**
- 53 API tests pass. The new `blocks.test.ts` covers:
  - who may block
  - the preview of what a block removes
  - removal of every product using the file, across catalogs and creators
  - the changes feed, notifications and appeals
  - refused uploads and their audit entry
  - unblocking, and restoring a removed product afterwards
- Type checks pass.
- On a local hub, through the website's own forms:
  - the Block link on a product's files, for moderators only
  - the Blocks tab, for moderators only (404 for the creator)
  - the file's page, then blocking: the product is gone, its creator notified and offered Appeal
  - a re-upload through the catalog API: refused, and audited
  - unblocking, then Restore
  - Fixed along the way: an empty reason gave a generic "Some of that isn't right"; it now says "Give a reason."

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Phase 3, part 2 (`docs/design.md`, "Next"): file blocks. Moderators block a file network-wide by its sha256, so a removed product can't come back under another name or catalog.

**Blocking**
- A file's page (Console → Blocks → a file) shows whether it's blocked and the products using it, so a moderator sees what a block removes before confirming ("Block and remove 2 products").
- Moderators reach it from a product's files (each has a Block link for them) or by pasting a sha256 into the Blocks tab, which also lists blocked files.
- Blocking a file:
  - removes every product with a revision using it. Each removal is audited as `product.remove` with the file, so creators are notified and can appeal it as before.
  - puts a `{type: "block", sha256}` change in the changes feed of every catalog hosting it, meaning: delete it whatever uses it. (t5de-catalog doesn't read the feed yet.)
  - refuses uploads with it from then on (409 `blocked`). Each attempt is audited as `file.blocked_upload` with the person and catalog, so moderators see who tried.
- Unblocking lets the file in again. The products it removed stay removed until a moderator restores them, one by one.
- Who: `product:remove` hub-wide (moderators and admins). The Blocks tab shows only for them.

**API**: `GET /api/v1/blocks`, and `GET`/`PUT`/`DELETE /api/v1/blocks/:sha256` (`docs/products.md`).

**Migration** `0013_file_blocks`: the `file_block` table, and a GIN index on revisions' file lists, so finding the products using a file doesn't scan every revision.

**Checks**
- 53 API tests pass. The new `blocks.test.ts` covers:
  - who may block
  - the preview of what a block removes
  - removal of every product using the file, across catalogs and creators
  - the changes feed, notifications and appeals
  - refused uploads and their audit entry
  - unblocking, and restoring a removed product afterwards
- Type checks pass.
- On a local hub, through the website's own forms:
  - the Block link on a product's files, for moderators only
  - the Blocks tab, for moderators only (404 for the creator)
  - the file's page, then blocking: the product is gone, its creator notified and offered Appeal
  - a re-upload through the catalog API: refused, and audited
  - unblocking, then Restore
  - Fixed along the way: an empty reason gave a generic "Some of that isn't right"; it now says "Give a reason."

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: dhkatz <[email protected]>

apps/api/src/products.ts

@@ -20,7 +20,7 @@ import { cleanHTML, maxDescription } from "./html";
 import type { ImvuClient } from "./imvu";
 import type { Signer } from "./keys";
 
-const { catalog, catalogChange, catalogMember, product, productInfoChange, productRevision, hosting, library, roleAssignment, user } =
+const { catalog, catalogChange, catalogMember, fileBlock, product, productInfoChange, productRevision, hosting, library, roleAssignment, user } =
   schema;
 
 export type Catalog = typeof catalog.$inferSelect;
@@ -63,6 +63,17 @@ export class ProductError extends Error {
   }
 }
 
+/** An upload with a blocked file (docs/products.md): refused, and the route audits who tried. */
+export class BlockedUpload extends ProductError {
+  constructor(
+    readonly personId: string,
+    readonly catalogId: string,
+    readonly files: FileEntry[],
+  ) {
+    super(409, "blocked", "This upload has a file T5DE blocks.");
+  }
+}
+
 const base32 = "abcdefghijklmnopqrstuvwxyz234567";
 export const newProductID = () =>
   [...crypto.getRandomValues(new Uint8Array(10))].map((b) => base32[b & 31]).join("");
@@ -260,6 +271,15 @@ export class Products {
     const parent = Number.isSafeInteger(body.parent) && body.parent > 0 ? body.parent : 0;
     const notes = (typeof body.notes === "string" ? body.notes.trim() : "").slice(0, 2000);
     const personId = claims.sub;
+    const blocked = new Set(
+      (
+        await this.db
+          .select({ sha256: fileBlock.sha256 })
+          .from(fileBlock)
+          .where(inArray(fileBlock.sha256, [...new Set(files.map((f) => f.sha256))]))
+      ).map((b) => b.sha256),
+    );
+    if (blocked.size) throw new BlockedUpload(personId, c.id, files.filter((f) => blocked.has(f.sha256)));
 
     const made = await this.db.transaction(async (tx) => {
       let p: Product;