fix(pkg): include auth/ and operator/ in published files[]

[Sentinel-Bluebuilder]

Summary

The 2.7.0 npm tarball ships incomplete: index.js re-exports from ./auth/ (adr36, keplr-signdoc, privy-cosmos-signer) and ./operator/ (auto-lease, batch-revoke, feegrant-history, plan-ownership), but neither directory was listed in package.json files[]. A fresh npm install [email protected] therefore breaks at import time:

```
Cannot find module '.../node_modules/blue-js-sdk/auth/adr36.js' imported from '.../node_modules/blue-js-sdk/index.js'
Cannot find module '.../node_modules/blue-js-sdk/operator/auto-lease.js' imported from '.../node_modules/blue-js-sdk/index.js'
```

This blocks the published Privy adapter (PrivyCosmosSigner, privyCosmosSignerFromMnemonic, etc.) from being usable downstream.

Reproduction (against the live npm tarball)

```bash
npm pack [email protected]
tar tzf blue-js-sdk-2.7.0.tgz | grep -E '(auth|operator)/'

(empty — neither directory is in the tarball)

```

Fix

Add `"auth/"` and `"operator/"` to files[].

Verification

After the patch, re-packing locally:

```bash
npm pack
tar tzf blue-js-sdk-2.7.0.tgz | grep -E '(auth|operator)/'
package/auth/adr36.js
package/auth/keplr-signdoc.js
package/auth/privy-cosmos-signer.js
package/operator/auto-lease.js
package/operator/batch-revoke.js
package/operator/feegrant-history.js
package/operator/plan-ownership.js
```

And import('blue-js-sdk') resolves cleanly with all 401 exports including PrivyCosmosSigner.

Test plan

• npm pack and confirm auth/ + operator/ appear in the tarball
• node -e "import('blue-js-sdk').then(m => console.log(Object.keys(m).length))" succeeds and reports >= 401 exports
• Republish 2.7.1 (or 2.7.0 retag) once merged

[Sentinel-Bluebuilder]

Superseded by #31 which adds the same fix plus CI tarball-install verification to prevent recurrence.