Expose additional FundingContribution accessors

Add public getters for `estimated_fee`, `inputs`, and `max_feerate`, and
elevate `feerate` from `pub(super)` to `pub`. Together with the existing
`value_added`, `outputs`, and `change_output`, this gives downstream
consumers of `TransactionType::Splice` (notably LDK Node, which updates
`PaymentDetails` from the broadcast callback) the data they need
without reaching into the raw transaction.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jkczyz

lightning/src/ln/funding.rs

@@ -710,10 +710,6 @@ impl_writeable_tlv_based!(FundingContribution, {
 });
 
 impl FundingContribution {
-	pub(super) fn feerate(&self) -> FeeRate {
-		self.feerate
-	}
-
 	pub(super) fn is_splice(&self) -> bool {
 		self.is_splice
 	}
@@ -731,6 +727,16 @@ impl FundingContribution {
 		self.value_added
 	}
 
+	/// Returns the estimated on-chain fee this contribution is responsible for paying.
+	pub fn estimated_fee(&self) -> Amount {
+		self.estimated_fee
+	}
+
+	/// Returns the inputs included in this contribution.
+	pub fn inputs(&self) -> &[FundingTxInput] {
+		&self.inputs
+	}
+
 	/// Returns the outputs (e.g., withdrawal destinations) included in this contribution.
 	///
 	/// This does not include the change output; see [`FundingContribution::change_output`].
@@ -746,6 +752,17 @@ impl FundingContribution {
 		self.change_output.as_ref()
 	}
 
+	/// Returns the fee rate used to select `inputs` (the minimum feerate).
+	pub fn feerate(&self) -> FeeRate {
+		self.feerate
+	}
+
+	/// Returns the maximum fee rate this contribution will accept as acceptor before rejecting
+	/// the splice.
+	pub fn max_feerate(&self) -> FeeRate {
+		self.max_feerate
+	}
+
 	pub(super) fn into_tx_parts(self) -> (Vec<FundingTxInput>, Vec<TxOut>) {
 		let FundingContribution { inputs, mut outputs, change_output, .. } = self;