fix(ai): remove accidental factory export

[hsubox76]

Bug introduced by #9201

Accidentally exported factory causing it to also export AIService and expose some references to internal-only typings, which breaks a strict typescript compile.

Fixes #9231

[changeset-bot]

🦋 Changeset detected

Latest commit: bb454db

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 2 packages

Name	Type
@firebase/ai	Patch
firebase	Patch

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[google-oss-bot]

Size Report ¹

Affected Products

• @firebase/ai

  Type	Base (f2ecae7)	Merge (78f0cba)	Diff
  browser	61.3 kB	61.3 kB	-8 B (-0.0%)
  main	64.9 kB	64.8 kB	-61 B (-0.1%)
  module	61.3 kB	61.3 kB	-8 B (-0.0%)

• firebase

  Type	Base (f2ecae7)	Merge (78f0cba)	Diff
  firebase-ai.js	48.4 kB	48.4 kB	-8 B (-0.0%)

Test Logs

• Base (f2ecae7): https://github.com/firebase/firebase-js-sdk/actions/runs/17301949064
• Merge (78f0cba): https://github.com/firebase/firebase-js-sdk/actions/runs/17308911236

1. https://storage.googleapis.com/firebase-sdk-metric-reports/qn4I99T4YV.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

No changes between base commit (f2ecae7) and merge commit (78f0cba).

Test Logs

• Base (f2ecae7): https://github.com/firebase/firebase-js-sdk/actions/runs/17301949064
• Merge (78f0cba): https://github.com/firebase/firebase-js-sdk/actions/runs/17308911236

1. https://storage.googleapis.com/firebase-sdk-metric-reports/uSKz5u9EUV.html