Orchestrator operations: register, cuts, service URI, reward caller

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### Is your feature request related to a problem?

The Explorer has no orchestrator operations. Registering (`transcoder`), updating the service URI, changing reward and fee cuts, and setting a LIP-118 reward caller.

### Describe the solution you'd like

An "Orchestrator" panel on the connected account's page, shown when the address is a registered orchestrator (or offers to register it), with:

- Register / update reward cut, fee cut, and service URI (`BondingManager.transcoder`, `ServiceRegistry.setServiceURI`)
- Set, view, and revoke the reward caller (`BondingManager.setRewardCaller`, `transcoderToRewardCaller`)

### Describe alternatives you've considered

- `livepeer_cli` on a node holding the keystore (defeats cold storage)
- `cast` against the contracts (works, but not a UI, and Arbiscan does not show the new BondingManager methods on the proxy page yet)
- Housing this in [livepeer/console](https://github.com/livepeer/console) instead. The Explorer seems the better fit since wallet connection and the protocol contracts are already wired up there, but either is fine; cross-reference if the console team wants it.

### Additional context

- LIP-118: https://github.com/livepeer/LIPs/blob/master/LIPs/LIP-118.md
- go-livepeer client support (in review): https://github.com/livepeer/go-livepeer/pull/4011

Start by locating the connected account page, wallet connection, and existing protocol contract wiring in the Explorer. Review the listed BondingManager and ServiceRegistry operations and the LIP-118 context, while confirming whether the Explorer or livepeer/console is the target. Done means an Orchestrator panel can register or update an orchestrator, manage cuts and service URI, and set, view, or revoke the reward caller.

Written by the indexing model from the issue text.