Merge rust-bitcoin/rust-bitcoin#6787: Move `from_script` to `Address` and drop `AddressExt`

### addresses/src/lib.rs
@@ -879,6 +879,38 @@ impl Address {
     ///
     pub fn is_spend_standard(&self) -> bool { self.address_type().is_some() }
 
+    /// Constructs a new [`Address`] from an output script (`scriptPubkey`).
+    ///
+    /// # Errors
+    ///
+    /// - [`FromScriptError::UnrecognizedScript`] if the given script is not p2pkh, p2sh, or
+    ///   SegWit program.
+    /// - [`FromScriptError::WitnessProgram`] if the given script has a valid SegWit version, but
+    ///   is not a valid witness program. See [`WitnessProgram::new`] for more details.
+    #[cfg(feature = "alloc")]
+    #[allow(clippy::missing_panics_doc)] // Slices have known lengths before array casts
+    pub fn from_script(
+        script: &ScriptPubKey,
+        params: impl Into<AddressParams>,
+    ) -> Result<Self, FromScriptError> {
+        let params = params.into();
+        if script.is_p2pkh() {
+            let bytes = script.as_bytes()[3..23].try_into().expect("statically 20B long");
+            let hash = PubkeyHash::from_byte_array(bytes);
+            Ok(Self::p2pkh(hash, params))
+        } else if script.is_p2sh() {
+            let bytes = script.as_bytes()[2..22].try_into().expect("statically 20B long");
+            let hash = ScriptHash::from_byte_array(bytes);
+            Ok(Self::p2sh_from_hash(hash, params))
+        } else if let Some(version) = script.witness_version() {
+            let program = WitnessProgram::new(version, &script.as_bytes()[2..])
+                .map_err(FromScriptError::WitnessProgram)?;
+            Ok(Self::from_witness_program(program, params))
+        } else {
+            Err(FromScriptError::UnrecognizedScript)
+        }
+    }
+
     /// Generates a script pubkey spending to this address.
     #[cfg(feature = "alloc")]
     pub fn script_pubkey(&self) -> ScriptPubKeyBuf {

### bitcoin/src/address.rs
@@ -40,10 +40,7 @@
 //! # }
 //! ```
 
-use addresses::witness_program::WitnessProgram;
-use crypto::key::PubkeyHash;
 use network::Network;
-use primitives::script::{ScriptHash, ScriptPubKey};
 
 use crate::network::Params;
 
@@ -77,39 +74,6 @@ impl From<Params> for AddressParams {
     fn from(params: Params) -> Self { Self::from(&params) }
 }
 
-mod sealed {
-    pub trait Sealed {}
-    impl Sealed for super::Address {}
-}
-
-crate::internal_macros::define_extension_trait! {
-    /// Extension functionality for the [`Address`] type
-    pub trait AddressExt impl for Address {
-        /// Constructs a new [`Address`] from an output script (`scriptPubkey`).
-        fn from_script(
-            script: &ScriptPubKey,
-            params: impl Into<AddressParams>,
-        ) -> Result<Address, FromScriptError> {
-            let params = params.into();
-            if script.is_p2pkh() {
-                let bytes = script.as_bytes()[3..23].try_into().expect("statically 20B long");
-                let hash = PubkeyHash::from_byte_array(bytes);
-                Ok(Self::p2pkh(hash, params))
-            } else if script.is_p2sh() {
-                let bytes = script.as_bytes()[2..22].try_into().expect("statically 20B long");
-                let hash = ScriptHash::from_byte_array(bytes);
-                Ok(Self::p2sh_from_hash(hash, params))
-            } else if let Some(version) = script.witness_version() {
-                let program = WitnessProgram::new(version, &script.as_bytes()[2..])
-                    .map_err(FromScriptError::WitnessProgram)?;
-                Ok(Self::from_witness_program(program, params))
-            } else {
-                Err(FromScriptError::UnrecognizedScript)
-            }
-        }
-    }
-}
-
 /// Error code for the address module.
 pub mod error {
     #[doc(inline)]
@@ -126,13 +90,15 @@ mod tests {
     use alloc::borrow::ToOwned;
     use alloc::string::ToString;
 
+    use addresses::witness_program::WitnessProgram;
+    use crypto::key::{FullPublicKey, LegacyPublicKey, PubkeyHash, XOnlyPublicKey};
     use hex::hex;
+    use primitives::witness_version::WitnessVersion;
 
     use super::*;
     use crate::network::params;
-    use crate::script::{RedeemScriptBuf, ScriptPubKeyBuf, WitnessScriptBuf};
-    use crate::witness_version::WitnessVersion;
-    use crate::{FullPublicKey, LegacyPublicKey, XOnlyPublicKey};
+    use crate::script::ScriptHash;
+    use crate::{RedeemScriptBuf, ScriptPubKeyBuf, WitnessScriptBuf};
 
     fn roundtrips(addr: &Address, params: AddressParams) {
         assert_eq!(

### bitcoin/src/lib.rs
@@ -103,7 +103,6 @@ pub mod ext {
     //! ```
     #[rustfmt::skip] // Use terse custom grouping.
     pub use crate::{
-        address::AddressExt as _,
         block::{BlockCheckedExt as _, HeaderExt as _},
         key::{FullPublicKeyExt as _, LegacyPublicKeyExt as _},
         network::NetworkExt as _,

### fuzz/fuzz_targets/bitcoin/arbitrary_script.rs
@@ -2,7 +2,7 @@
 #![cfg_attr(not(fuzzing), allow(unused))]
 
 use arbitrary::{Arbitrary, Unstructured};
-use bitcoin::address::{Address, AddressExt as _, AddressParams};
+use bitcoin::address::{Address, AddressParams};
 use bitcoin::encoding::encode_to_vec;
 use bitcoin::script::{self, ScriptBuf, ScriptExt as _, ScriptPubKeyExt as _};
 use bitcoin::Network;