Visualizer: support live logs from Loki

[ch1bo]

Supports scenarios with a loki: "localhost:3100" entry (or any other endpoint) and visualize the logs from multiple nodes (also the immdb-server mockup) by parsing them into the right format.

A quick demo using the local 2025-11-demo setup (without WAN emulation, but 200ms latency on the topology to see something):

2025-11-demo-visualization-2025-12-05_16.13.21.mp4

This is very hacky and the useLokiWebSocket component has these shortcuts/problems (FIXME!):

• Hard-coded 200ms latencies in prototype.yaml topology. One can see the discrepancy when packages are still animated as in flight, while the received event already happened.
• Hard-coded HOST_PORT_TO_NODE mapping to determine sender/recipient nodes in topology from loglines.
• Slots in events are mostly unavailable from log lines and not correct
• Event ids are mostly garbage because send/receive events are often not containing unique identifiers or have things elided. This also prevents proper matching of send/receive events for accurate traveling animations.
• Transaction "batches" are visualized as single green blocks (and could be mistaken as single transactions, but each is a couple hundred kilobytes!)
• Missing: RBGenerated, EBGenerated and TxGenerated events are not covered (yet)

In conclusion, the visualization could be further improved with:

• Better trace output at the source with consistent identifiers
• Conversion "further upstream" (also benefiting trace verifier integration)
• Automatically determine topology, or move mapping at least into the topology json/yaml
• Animation should not use static latency from topology (but match up send/receive events for accurate travel time)
• Indicate sizes as varying length blocks (incorporating a rough bandwidth measure?)
• Start/End sending/receiving or otherwise more granular events (requests?)