fix(ci): generate the Prisma client before running tests

The pipeline has been red on every run since at least ae0c34f. npm ci
installs dependencies but the Prisma client is generated into
src/generated/prisma, which is gitignored — so a fresh CI checkout has no
client and anything importing src/lib/db.ts fails with 'Cannot find package
@/generated/prisma/client' before a single assertion runs.

prisma generate reads only the schema, so it needs no database and no
secrets.

Worth noting why this went unnoticed for a dozen commits: a pipeline that
is always red carries no signal, so it stopped being read.

.gitea/workflows/ci.yml

@@ -13,6 +13,15 @@ jobs:
           node-version: 22
       - name: Install
         run: npm ci
+      # The Prisma client is generated into src/generated/prisma, which is
+      # gitignored — so a fresh checkout has no client and every test that
+      # reaches src/lib/db.ts dies on "Cannot find package
+      # '@/generated/prisma/client'". Schema-only, so it needs no database.
+      # Without this the pipeline had been red on every run since at least
+      # ae0c34f, which is how the failure stayed invisible: it looked like
+      # the normal colour.
+      - name: Generate Prisma client
+        run: npx prisma generate
       # Advisory until the pre-existing lint debt is cleared (2026-07-19:
       # ~20 errors across budget/insights/shared pages) — then make blocking.
       - name: Lint (advisory)