Owns the interaction with OTP's :crashdump_viewer parser (a globally named gen_server): starts it on demand, serializes dump loads, receives the parser's progress reports and broadcasts them, and decodes its records into maps for the Crashdump page.

Progress: while loading, this server registers itself under the name the parser reports to (:cdv_progress_handler, a no-op destination when unregistered) and receives {:progress, {:ok, phase | percent | :done}} / {:progress, {:error, reason}} messages, re-broadcast on the "crashdump" PubSub topic.

Decoding: #general_info{}/#proc{} records are converted by zipping their documented field order over the tuple - a dump/record from a different OTP release with more or fewer fields degrades to the fields both sides know instead of crashing.