sv2: serve the Template Distribution Protocol over Noise

COMPAT.md

@@ -72,6 +72,7 @@ Full `/tx/:txid` JSON still has `vin[]`. Electrum has no outspend-vin surface.
 | Package submit | RPC `submitpackage` / Esplora `POST /txs/package` (no P2P package command) | BIP331 wire |
 | Pruning / GUI | Unpruned: `seqsigwit.body`. `--prune-seqsigwit`: watermark + `NETWORK_LIMITED`, kept witness is 288 height files under `store/seqsigwit.window/` plus a RAM cap (`--prune-seqsigwit-ram-threshold-bytes`, `0` = files only). Not a rolling stem. Not Core `-prune` of headers/txout | Supported |
 | Mining template RPC | `getblocktemplate` / `getmininginfo` / `prioritisetransaction` (selector; no stratum) | GBT + stratum / pool stack |
+| SV2 Template Distribution | In-process TDP v2 server over Noise NX (`--sv2-tp-listen`, default off): `NewTemplate` / `SetNewPrevHash` per tip, `RequestTransactionData`, `SubmitSolution` → block accept. No templates during IBD; last 3 per session. No plaintext, no pool / JD roles | No TDP in Core; sv2-apps `bitcoin-core-sv2` bridges Core's IPC mining interface to TDP |
 | Wallets | Electrum clients (requires `--shindex`) | Descriptor + legacy |
 | Scripthash index | Optional (`--shindex`, default **off**); bulk at tip when on | External ElectrumX / Fulcrum; Core `-txindex` is different (txid→block) |
 | JSON-RPC | Documented **subset** ([`docs/rpc.md`](./docs/rpc.md)); Bearer token or opt-in Core cookie (`--rpc-cookie-file`), no `--rpcuser` / `--rpcpassword`; `rbitcoin-cli`. `--rpc-work-queue` defaults to **16** (HTTP occupancy, 503 when full; **0** is that default); a JSON-RPC array is one POST | Full Core RPC; `-rpcworkqueue` is in-flight HTTP jobs (503) |