feat(truapi-server): add wire and chain infrastructure

[pgherveou]

Adds the truapi-server wire/chain infrastructure: frame codec helpers, dispatcher registration, subscription plumbing, host JSON-RPC client, and chain runtime mechanics.

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Stack

Part of the Rust core runtime port (umbrella: #104), split into a reviewable stack. Merge bottom-up.

1. feat(truapi): add testing API and versioned wiring #248 — truapi: testing API + versioned wiring
2. feat(truapi-platform): add host capability traits #249 — truapi-platform: host capability traits
3. feat(truapi-codegen): emit Rust dispatcher, wire table, and host callbacks #254 — truapi-codegen: Rust dispatcher + wire table
4. feat(truapi-server): add host logic primitives #255 — truapi-server: host logic primitives
5. feat(truapi-server): add wire and chain infrastructure #256 — truapi-server: wire and chain infrastructure 👈
6. feat(truapi-server): add platform runtime and host bridge #250 — truapi-server: platform runtime and host bridge
7. feat(host-wasm): add @parity/truapi-host-wasm runtime #252 — host-wasm: @parity/truapi-host-wasm runtime
8. chore: docs, CI, tooling, and dotli integration for the Rust core #253 — docs, CI, tooling, dotli integration

Local verification

• cargo build --workspace --all-targets --all-features
• cargo +nightly fmt --check
• cargo +nightly clippy --workspace --all-targets --all-features -- -D warnings
• cargo test --workspace --all-features