feat(ai): Add Live API transcriptions

[dlarocque]

Adds support for Live API transcriptions.

API Proposal: go/firebase-ai-bidi-transcripts (internal)

[changeset-bot]

🦋 Changeset detected

Latest commit: e4c7125

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

This PR includes changesets to release 2 packages

Name	Type
firebase	Minor
@firebase/ai	Minor

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[github-actions]

Vertex AI Mock Responses Check ⚠️

A newer major version of the mock responses for Vertex AI unit tests is available. update_vertexai_responses.sh should be updated to clone the latest version of the responses: v15.0

[google-oss-bot]

Size Report ¹

Affected Products

• @firebase/ai

  Type	Base (22e0a1a)	Merge (b60dc46)	Diff
  browser	65.1 kB	65.4 kB	+240 B (+0.4%)
  main	69.0 kB	69.2 kB	+240 B (+0.3%)
  module	65.1 kB	65.4 kB	+240 B (+0.4%)

• firebase

  Type	Base (22e0a1a)	Merge (b60dc46)	Diff
  firebase-ai.js	51.3 kB	51.4 kB	+114 B (+0.2%)

Test Logs

• Base (22e0a1a): https://github.com/firebase/firebase-js-sdk/actions/runs/18658284611
• Merge (b60dc46): https://github.com/firebase/firebase-js-sdk/actions/runs/18687641608

1. https://storage.googleapis.com/firebase-sdk-metric-reports/CrXKDDY8LZ.html

[google-oss-bot]

Size Analysis Report ¹

Affected Products

• @firebase/ai

  • LiveGenerativeModel

    Size

    Type	Base (22e0a1a)	Merge (b60dc46)	Diff
    size	13.8 kB	13.9 kB	+120 B (+0.9%)
    size-with-ext-deps	31.5 kB	31.6 kB	+120 B (+0.4%)

  • getLiveGenerativeModel

    Size

    Type	Base (22e0a1a)	Merge (b60dc46)	Diff
    size	16.2 kB	16.3 kB	+120 B (+0.7%)
    size-with-ext-deps	33.9 kB	34.1 kB	+120 B (+0.4%)

Test Logs

• Base (22e0a1a): https://github.com/firebase/firebase-js-sdk/actions/runs/18658284611
• Merge (b60dc46): https://github.com/firebase/firebase-js-sdk/actions/runs/18687641608

1. https://storage.googleapis.com/firebase-sdk-metric-reports/JzoeB0uvtK.html

[github-actions]

Changeset File Check ✅

• No modified packages are missing from the changeset file.
• No changeset formatting errors detected.

[hsubox76]

Neat. I didn't know you could do this

[dlarocque]

Merging without TW approval to get this into the M172 release. Documentation review can happen in the reference documentation import CL, or retroactively on this PR.