Add Image to text AI pipeline support

[mjh1]

What does this pull request do? Explain your changes. (required)

Adds support for the ai-worker pipeline which implements a image-to-text model (default https://huggingface.co/Salesforce/blip-image-captioning-large)

Corresponding AI-Worker PR:
livepeer/ai-worker#223

Specific updates (required)

How did you test each of these updates (required)

Tested by running the gateway and worker locally.

Does this pull request close any open issues?

Checklist:

• Read the contribution guide
• make runs successfully
• All tests in ./test.sh pass
• README and other documentation updated
• Pending changelog updated

[codecov]

Codecov Report

Attention: Patch coverage is 1.29032% with 153 lines in your changes missing coverage. Please review.

Project coverage is 35.92244%. Comparing base (c41f3c4) to head (ef6a2a8).
Report is 7 commits behind head on ai-video.

Files with missing lines	Patch %	Lines
server/ai_process.go	0.00000%	84 Missing ⚠️
server/ai_http.go	0.00000%	39 Missing ⚠️
core/ai_worker.go	0.00000%	30 Missing ⚠️

Additional details and impacted files

@@                 Coverage Diff                 @@
##            ai-video       #3202         +/-   ##
===================================================
- Coverage   36.07820%   35.92244%   -0.15576%     
===================================================
  Files            124         124                 
  Lines          34525       34658        +133     
===================================================
- Hits           12456       12450          -6     
- Misses         21381       21520        +139     
  Partials         688         688                 

Files with missing lines	Coverage Δ
core/ai.go	58.51852% <ø> (ø)
core/capabilities.go	81.69336% <100.00000%> (+0.04198%)	⬆️
server/ai_mediaserver.go	10.37037% <100.00000%> (+0.33320%)	⬆️
server/rpc.go	68.07229% <ø> (ø)
core/ai_worker.go	34.22104% <0.00000%> (-0.79258%)	⬇️
server/ai_http.go	10.32702% <0.00000%> (-0.74309%)	⬇️
server/ai_process.go	0.00000% <0.00000%> (ø)

... and 1 file with indirect coverage changes

---

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Files with missing lines	Coverage Δ
core/ai.go	58.51852% <ø> (ø)
core/capabilities.go	81.69336% <100.00000%> (+0.04198%)	⬆️
server/ai_mediaserver.go	10.37037% <100.00000%> (+0.33320%)	⬆️
server/rpc.go	68.07229% <ø> (ø)
core/ai_worker.go	34.22104% <0.00000%> (-0.79258%)	⬇️
server/ai_http.go	10.32702% <0.00000%> (-0.74309%)	⬇️
server/ai_process.go	0.00000% <0.00000%> (ø)

... and 1 file with indirect coverage changes

[mjh1]

I've merged in the latest ai-video and resolved the conflicts etc so this is ready to review now 🙏

[rickstaa]

@mjh1 I tested that his works on-chain. Very fast and strong pipeline (i.e. 200ms).