refactor: port Firo watcher from RPC to ElectrumX

[navidR]

This PR ports the watcher’s Firo path from firod RPC to ElectrumX by replacing the Firo RPC connector/scanner wiring with FiroElectrumXNetwork, FiroElectrumXScanner, FiroObservationExtractor, and the Firo ElectrumX scanner health check, while updating config/env names from firo.rpc to firo.electrumx.

Note: Watcher depends on new ElectrumX exports from the scanner and health-check packages, so this PR can only pass install/tests after those PRs are merged, released, and the watcher lockfile is updated to consume the new package versions.

[RaaCT0R]

🚫 Required Change

Seems you've committed your changes after the dev branch. You need to do them after the snapshot-firo-release branch. You should create the PR targeted to snapshot-firo-release too. Because there are some changes in the dev that should not be included in the next release which is focused only on Firo integration (Note that it's only for watcher repo. The guard-service repo is okay and should follow the dev branch).

[navidR]

🚫 Required Change

Seems you've committed your changes after the dev branch. You need to do them after the snapshot-firo-release branch. You should create the PR targeted to snapshot-firo-release too. Because there are some changes in the dev that should not be included in the next release which is focused only on Firo integration (Note that it's only for watcher repo. The guard-service repo is okay and should follow the dev branch).

Thanks. Addressed.