fix(audience): build @imtbl/audience in publish workflow

The publish workflow's build step (`pnpm build`) runs nx with an explicit
project list — `@imtbl/sdk,@imtbl/checkout-widgets`. `@imtbl/audience` was
missing, so its `dist/` was never produced before `pnpm pack-npm-packages`
ran. Because `@imtbl/audience/package.json` declares `"files": ["dist"]`,
`npm pack` then shipped tarballs containing only `package.json` and
`LICENSE.md` — no compiled output.

Symptom on the registry today:
- `@imtbl/audience@0.0.1-alpha.0` and `@imtbl/audience@2.15.0-alpha.21`
  both install successfully but contain no `dist/`. Anything trying to
  `import { Audience } from '@imtbl/audience'` fails at module resolution
  because `package.json#main` points at `dist/node/index.cjs` and the
  file doesn't exist.

PR #2843 added `@imtbl/audience` to the version-seeding step, so it gets
version-bumped on every publish — but the build step was never updated
in lockstep. Add it here, and rename the workflow step labels so they
match what's actually being built/packed.

After this lands, the next publish should produce a real tarball. Verify
locally with:

    pnpm build
    cd packages/audience/sdk && pnpm pack --dry-run

The dry-run output should list files under `dist/node/`, `dist/browser/`,
and `dist/types/`.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: ImmutableJeffrey

.github/workflows/publish.yaml

@@ -104,10 +104,10 @@ jobs:
       - name: Setup new package versions
         run: pnpm nx release version --specifier ${{ env.RELEASE_TYPE }} $( ${{ env.DRY_RUN }} && echo "--dry-run" || echo "")
 
-      - name: Build SDK & Checkout Widgets
+      - name: Build SDK, Checkout Widgets & Audience
         run: pnpm build
 
-      - name: Pack SDK & Checkout Widgets packages and dependencies
+      - name: Pack SDK, Checkout Widgets & Audience packages and dependencies
         run: pnpm pack-npm-packages
 
       # ! Do NOT remove any of these attestation subject paths - this will cause a Sev 0 incident !

package.json

@@ -56,7 +56,7 @@
     "responselike": "^2.0.0"
   },
   "scripts": {
-    "build": "nx run-many -p @imtbl/sdk,@imtbl/checkout-widgets -t build",
+    "build": "nx run-many -p @imtbl/sdk,@imtbl/checkout-widgets,@imtbl/audience -t build",
     "build:examples": "pnpm --recursive --filter '@examples/**' build",
     "build:onlysdk": "NODE_OPTIONS=--max-old-space-size=14366 nx run-many --target=build --projects=@imtbl/sdk && pnpm syncpack:format",
     "dev": "FORCE_COLOR=1 pnpm --filter @imtbl/sdk... --filter @imtbl/checkout-widgets... run transpile && pnpm --parallel --filter @imtbl/sdk... --filter @imtbl/checkout-widgets... run transpile --watch",