Fix echo registry auth via .npmrc env var interpolation, restore registry-url

Root cause was npm config precedence: the project-level .npmrc (checked
into the repo) always overrides user-level config, so its literal blank
auth token lines were shadowing whatever the separate "npm config set"
step wrote at the user level - regardless of registry-url on setup-node.

- .npmrc now resolves tokens via ${ECHO_LIBRARIES_ACCESS_KEY} at read
  time instead of committing blank placeholders, so the project-level
  config itself carries valid auth.
- Restored registry-url on setup-node in ci.yml/release.yml (safe now
  that .npmrc's interpolated values take precedence over it either way).
- Removed the now-redundant "Configure echohq auth" npm config set steps.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

Author: cx-atish-jadhav

.github/workflows/ci.yml

@@ -34,12 +34,7 @@ jobs:
         uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.11.0
-      - name: Configure echohq auth (both hosts)
-        env:
-          ECHO_LIBRARIES_ACCESS_KEY: ${{ secrets.ECHO_LIBRARIES_ACCESS_KEY }}
-        run: |
-          npm config set //npm.echohq.com/:_authToken "${ECHO_LIBRARIES_ACCESS_KEY}"
-          npm config set //packages.echohq.com/:_authToken "${ECHO_LIBRARIES_ACCESS_KEY}"
+          registry-url: https://npm.echohq.com/
       - run: npm ci
         env:
           ECHO_LIBRARIES_ACCESS_KEY: ${{ secrets.ECHO_LIBRARIES_ACCESS_KEY }}

.github/workflows/release.yml

@@ -99,14 +99,7 @@ jobs:
       - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
         with:
           node-version: 22.11.0
-
-      # CONFIGURE ECHOHQ AUTH
-      - name: Configure echohq auth (both hosts)
-        env:
-          ECHO_LIBRARIES_ACCESS_KEY: ${{ secrets.ECHO_LIBRARIES_ACCESS_KEY }}
-        run: |
-          npm config set //npm.echohq.com/:_authToken "${ECHO_LIBRARIES_ACCESS_KEY}"
-          npm config set //packages.echohq.com/:_authToken "${ECHO_LIBRARIES_ACCESS_KEY}"
+          registry-url: https://npm.echohq.com/
 
       # CONFIGURE GITHUB PACKAGES AUTH FOR PUBLISH
       - name: Configure GitHub Packages auth

.npmrc

@@ -1,6 +1,6 @@
 # Default registry for most packages
 registry=https://npm.echohq.com/
-//npm.echohq.com/:_authToken=
-//packages.echohq.com/:_authToken=
+//npm.echohq.com/:_authToken=${ECHO_LIBRARIES_ACCESS_KEY}
+//packages.echohq.com/:_authToken=${ECHO_LIBRARIES_ACCESS_KEY}
 always-auth=true
 ignore-scripts=true