Add flag to use AI ServiceRegistry contract address for Livepeer AI Subnet

[leszko]

For the time being we're using a separate ServiceRegistry contract for the Livepeer AI Subnet. This PR introduces a flag to decide on using AI ServiceRegistry.

Here's a list of O and their Service URI difference between Livepeer Network and Livepeer AI Subnet.

Orchestrator	Service URI	AI Service URI
0x847791cBF03be716A7fe9Dc8c9Affe17Bd49Ae5e	https://livepeertothemoon.stronk.rocks:8995	https://ai.stronk.rocks:8991
0x0d509d8b46B072f8fc330942B2e3cC0AC34d6d8D	https://transcoder.navigare-necesse-est.work:8931	https://ai.navigare-necesse-est.work:7953
0xd00354656922168815Fcd1e51CBddB9e359e3C7F	https://orch.xodeapp.xyz:8935	https://livepeer-ai.xodeapp.xyz:18936
0x9D5611bf0DAdddb4441A709141d9229d7F6b3e47	https://cdotlpt.com:8935	https://ai.deficrypto.dev:8936
0x5BdEedCA9c6346B0CE6b17ffa8227A4DACE37039	https://orch.transcode.ninja:8935	https://orch.transcode.ninja:8936
0x3b28a7D785356Dc67C7970666747e042305bfB79	https://livepeer-router.0xb79.com:5555	https://ai-subnet.ad-astra.video:9955
0x10e0A91E652b05e9C7449ff457Cf2E96C3037fB7	https://interptr.link:8935	https://204.12.245.134:8936
0x22a48674a6FDf9335d89B6DbC05C38e2dc181475	https://orchestrator.work:8936	https://ai.vid-wave.xyz:8937
0x6CB1Ce2516FB7d211038420a8Cf9a843c7bD3B08	https://livepeerservice.world:8935	https://livepeerservice.ddns.net:8936
0xBe8770603dAf200b1Fa136aD354BA854928e602B	https://titan-node-service.com:8936	https://chase.titan-node-orch.com:8936
0xeB6Dde1A9E305Fe8b1556056bBDF14d25D3a878b	https://livepeer.3earth.net:8936	https://ai.3earth.net:28936
0xBD677e96a755207D348578727AA57A512C2022Bd	https://arjo-node.uk:9000	https://ai.arjo-node.uk:6500
0x9D61ae5875E89036FBf6059f3116d01a22ACe3C8	https://null.anlivepeer.com:8935	https://ai.nullworks.xyz:9824
0x10b21af759129F32C6064ADfb85d3eA2a8C0209c	https://mangolpt.com:8935	https://ai.mangolpt.com:8936
0x5Ea1B47194B98044fCA8a187237d9704C91478CA	https://orch.thomshutt.com:8935	https://orch.thomshutt.com:8936
0x525419FF5707190389bfb5C87c375D710F5fCb0E	https://vin-node.com:8935	https://ai.vin-node.com:8836
0x66970F8B4a5376ED7961e8633a83809E49Ad809d	https://lead-sail.work:8395	https://server.ai-bitbender.xyz:8939
0xD93e0A15511935889AeC76f79D54DFf0e27af82e	https://czternascie.brzeczyszczykiewicz.work:8934	https://ai.brzeczyszczykiewicz.work:8935
0xA6A9eB29e786B5233bD99C0bA28bE882fe954a0e	https://18.116.254.47:8935	https://18.217.142.172:8936
0x16a72bdb3017196825BC53809b87F96fbEE31F6C		https://86.94.162.140:9999
0xf909aC60C647a14DB3663dA5EcF5F8eCbE324395	https://adexlabs.live:8935	https://adexlabs.go.ro:8936
0xd4C467d8c13752AB7bb9711bc77De2a9f52a65f6	https://2.9.173.59:8935	https://2.9.173.59:8936
0xDef1C70578B2B5e8589a42e26980687fc5153079	https://compute.speedybird.xyz:443	https://livepeer-ai.speedybird.xyz:18936
0x980998E39D29Dc5A92e7403fC9cD47e68b63Ad5f	https://82.65.173.160:8935	https://82.65.173.160:8936
0x43942A3B2883BA56C67750dE398d4F1D1b3A3fdB	https://128.140.93.150:8935	https://ai.joincluster.com:8936
0x5CaaaB7626eDc7123cF8484EdBC66a875DD32CC9	https://lpt.sundara.tv:8935	https://ai.sundara.tv:8936
0xD603D6BF88aa061Fcab8FA552026694a7FD005cE	https://kiloutcorp.link:8935	https://kilout.link:8988
0x104a7CA059A35Fd4dEF5Ecb16600B2CaA1Fe1361	https://node.eliteencoder.net:8935	https://ai-subnet.eliteencoder.net:8936
0x22b1BCC0C0Db224BFC56c9b95a2DB407548666eE	https://45.153.35.151:8935	https://45.153.35.148:20080
0xdc28F2842810D1a013aD51DE174D02eABA192dC7	https://pon-eth.com:8998	https://ai.pon-eth.com:9125
0x5d11abD838073Df76E32c495F97Fd3239EabB9Fb	https://chase.titan-node-orch.com:8935	https://chase.titan-node-orch.com:8940
0x5263E0Ce3a97B634D8828CE4337aD0F70B30B077	https://livepeer.compute-node.xyz:9935	https://livepeer-ai.open-pool.com:28936
0x10742714F33f3d804E3FA489618b5c3Ca12a6dF7	https://liverouter.xyz:9935	https://papa-ai.liverouter.xyz:18936
0x74a7839094b7f723b2C1C915e88928F49dFdc21f	https://node.livepeer-utopia.xyz:8937	https://ai.livepeer-utopia.xyz:18937
0xbB4c38FaE6Eef586F521E369117354E43ac7dD5B	https://livepeer.mozcomputing.dev:8935	https://livepeer-ai.mozcomputing.dev:8936
0xA05f25eA504D39C524427cCa2beb52E597c3a98B	https://lucky-transcoder-node.asuscomm.cn:8935	https://lucky-transcoder-node.asuscomm.com:9935
0xD7775cF383481512C62e030e42e51aB7EC2adAEe	https://evanmtranscode.ddns.net:8395	https://evanmtranscode.ddns.net:8396
0x2e3a21ae7cDEb48F57fcaD1cE16b258d5502aC05	https://livepeer.ultimaratio.link:8935	https://ai.ultimaratio.link:18936

[rickstaa]

LGTM. I did notice a problem at the cli side when the orch URL is an empty string but will create a seperate pull request for this.