docs(consensus): add extraction markers for guided code review

Add @@start/@@end comment markers to key RNG pipeline sections for
automated documentation extraction. No logic changes.

src/ripple/app/consensus/RCLConsensus.cpp

@@ -1268,6 +1268,7 @@ RCLConsensus::Adaptor::hasAnyReveals() const
 uint256
 RCLConsensus::Adaptor::buildCommitSet(LedgerIndex seq)
 {
+    //@@start rng-build-commit-set
     auto map =
         std::make_shared<SHAMap>(SHAMapType::TRANSACTION, app_.getNodeFamily());
     map->setUnbacked();
@@ -1320,11 +1321,13 @@ RCLConsensus::Adaptor::buildCommitSet(LedgerIndex seq)
     JLOG(j_.debug()) << "RNG: built commitSet SHAMap hash=" << hash
                      << " entries=" << pendingCommits_.size();
     return hash;
+    //@@end rng-build-commit-set
 }
 
 uint256
 RCLConsensus::Adaptor::buildEntropySet(LedgerIndex seq)
 {
+    //@@start rng-build-entropy-set
     auto map =
         std::make_shared<SHAMap>(SHAMapType::TRANSACTION, app_.getNodeFamily());
     map->setUnbacked();
@@ -1374,6 +1377,7 @@ RCLConsensus::Adaptor::buildEntropySet(LedgerIndex seq)
     JLOG(j_.debug()) << "RNG: built entropySet SHAMap hash=" << hash
                      << " entries=" << pendingReveals_.size();
     return hash;
+    //@@end rng-build-entropy-set
 }
 
 void
@@ -1684,6 +1688,7 @@ RCLConsensus::Adaptor::injectEntropyPseudoTx(
     uint256 finalEntropy;
     bool hasEntropy = false;
 
+    //@@start rng-inject-entropy-selection
     // Calculate entropy from collected reveals
     if (app_.config().standalone())
     {
@@ -1738,7 +1743,9 @@ RCLConsensus::Adaptor::injectEntropyPseudoTx(
                             << " for ledger " << seq;
         }
     }
+    //@@end rng-inject-entropy-selection
 
+    //@@start rng-inject-pseudotx
     // Synthesize and inject the pseudo-transaction
     if (hasEntropy)
     {
@@ -1760,6 +1767,7 @@ RCLConsensus::Adaptor::injectEntropyPseudoTx(
 
         retriableTxs.insert(std::make_shared<STTx>(std::move(tx)));
     }
+    //@@end rng-inject-pseudotx
 
     // Reset RNG state for next round
     clearRngState();
@@ -1779,6 +1787,7 @@ RCLConsensus::Adaptor::harvestRngData(
                      << " commit=" << (position.myCommitment ? "yes" : "no")
                      << " reveal=" << (position.myReveal ? "yes" : "no");
 
+    //@@start rng-harvest-trust-and-reveal-verification
     // Reject data from validators not in the active UNL
     if (!isUNLReportMember(nodeId))
     {
@@ -1855,6 +1864,7 @@ RCLConsensus::Adaptor::harvestRngData(
                              << *position.myReveal;
         }
     }
+    //@@end rng-harvest-trust-and-reveal-verification
 
     // Store proposal proofs for embedding in SHAMap entries.
     // commitProofs_: only seq=0 (commitments always ride on seq=0,

src/ripple/app/consensus/RCLCxPeerPos.h

@@ -105,6 +105,7 @@ struct ExtendedPosition
     //     entropy result is verified deterministically from collected reveals.
     //   - Leaves (myCommitment, myReveal) are also excluded — they are
     //     per-validator data unique to each proposer.
+    //@@start rng-extended-position-equality
     bool
     operator==(ExtendedPosition const& other) const
     {
@@ -141,8 +142,10 @@ struct ExtendedPosition
     {
         return pos.txSetHash != hash;
     }
+    //@@end rng-extended-position-equality
 
     // CRITICAL: Include ALL fields for signing (prevents stripping attacks)
+    //@@start rng-extended-position-serialize
     void
     add(Serializer& s) const
     {
@@ -173,6 +176,7 @@ struct ExtendedPosition
         if (myReveal)
             s.addBitString(*myReveal);
     }
+    //@@end rng-extended-position-serialize
 
     Json::Value
     getJson() const
@@ -191,6 +195,7 @@ struct ExtendedPosition
         Returns nullopt if the payload is malformed (truncated for the
         flags advertised).
     */
+    //@@start rng-extended-position-deserialize
     static std::optional<ExtendedPosition>
     fromSerialIter(SerialIter& sit, std::size_t totalSize)
     {
@@ -235,6 +240,7 @@ struct ExtendedPosition
 
         return pos;
     }
+    //@@end rng-extended-position-deserialize
 };
 
 // For logging/debugging - returns txSetHash as string

src/ripple/app/ledger/impl/BuildLedger.cpp

@@ -104,6 +104,7 @@ applyTransactions(
     bool certainRetry = true;
     std::size_t count = 0;
 
+    //@@start rng-entropy-first-application
     // CRITICAL: Apply consensus entropy pseudo-tx FIRST before any other
     // transactions. This ensures hooks can read entropy during this ledger.
     for (auto it = txns.begin(); it != txns.end(); /* manual */)
@@ -142,6 +143,7 @@ applyTransactions(
         it = txns.erase(it);
         break;  // Only one entropy tx per ledger
     }
+    //@@end rng-entropy-first-application
 
     // Attempt to apply all of the retriable transactions
     for (int pass = 0; pass < LEDGER_TOTAL_PASSES; ++pass)

src/ripple/app/tx/impl/Change.cpp

@@ -238,6 +238,7 @@ Change::applyConsensusEntropy()
 {
     auto const entropy = ctx_.tx.getFieldH256(sfDigest);
 
+    //@@start rng-consensus-entropy-sle-write
     auto sle = view().peek(keylet::consensusEntropy());
     bool const created = !sle;
 
@@ -255,6 +256,7 @@ Change::applyConsensusEntropy()
         view().insert(sle);
     else
         view().update(sle);
+    //@@end rng-consensus-entropy-sle-write
 
     JLOG(j_.info()) << "ConsensusEntropy: updated entropy to " << entropy
                     << " at ledger " << view().info().seq;

src/ripple/consensus/Consensus.h

@@ -1409,6 +1409,7 @@ Consensus<Adaptor>::phaseEstablish()
         return;
     }
 
+    //@@start rng-phase-establish-substates
     // --- RNG Sub-state Checkpoints (if adaptor supports RNG) ---
     // These sub-states use union convergence (not avalanche).
     // Commits and reveals arrive piggybacked on proposals, so by the time
@@ -1590,6 +1591,7 @@ Consensus<Adaptor>::phaseEstablish()
                 return;
         }
     }
+    //@@end rng-phase-establish-substates
 
     JLOG(j_.info()) << "Converge cutoff (" << currPeerPositions_.size()
                     << " participants)";