Rename UnsignedFixedDecimal to UnsignedDecimal (#6143)

# Description: 

Renames the UnsignedFixedDecimal type to UnsignedDecimal across multiple
files in the fixed_decimal module. This includes updates to:
- Rust source files
- Documentation
- Test files
- Dart bindings
- Diplomat coverage allowlist

The rename maintains the existing functionality while providing a more
concise type name.

Related Issues: #5065,
#6144


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components/experimental/src/duration/format.rs

@@ -8,7 +8,7 @@ use super::validated_options::Unit;
 use core::fmt;
 use core::fmt::Write;
 use either::Either;
-use fixed_decimal::{SignDisplay, SignedFixedDecimal, UnsignedFixedDecimal};
+use fixed_decimal::{SignDisplay, SignedFixedDecimal, UnsignedDecimal};
 use icu_decimal::FormattedDecimal;
 use smallvec::SmallVec;
 use writeable::{adapters::WithPart, PartsWrite, Writeable};
@@ -238,15 +238,15 @@ impl FormattedDuration<'_> {
         ] {
             if style == FieldStyle::Fractional {
                 let val = val + prev_val / 1000;
-                prev_formatted.absolute = UnsignedFixedDecimal::from(val % 1000)
+                prev_formatted.absolute = UnsignedDecimal::from(val % 1000)
                     .concatenated_end(prev_formatted.absolute.multiplied_pow10(-3))
                     .unwrap();
 
                 prev_val = val;
             } else {
                 return SignedFixedDecimal::new(
                     prev_formatted.sign,
-                    UnsignedFixedDecimal::from(val)
+                    UnsignedDecimal::from(val)
                         .concatenated_end(prev_formatted.absolute.multiplied_pow10(-3))
                         .unwrap(),
                 );

ffi/capi/src/fixed_decimal.rs

@@ -191,42 +191,36 @@ pub mod ffi {
             )))
         }
 
-        #[diplomat::rust_link(fixed_decimal::UnsignedFixedDecimal::digit_at, FnInStruct)]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::digit_at, FnInStruct)]
         pub fn digit_at(&self, magnitude: i16) -> u8 {
             self.0.absolute.digit_at(magnitude)
         }
 
-        #[diplomat::rust_link(fixed_decimal::UnsignedFixedDecimal::magnitude_range, FnInStruct)]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::magnitude_range, FnInStruct)]
         #[diplomat::attr(auto, getter)]
         pub fn magnitude_start(&self) -> i16 {
             *self.0.absolute.magnitude_range().start()
         }
 
-        #[diplomat::rust_link(fixed_decimal::UnsignedFixedDecimal::magnitude_range, FnInStruct)]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::magnitude_range, FnInStruct)]
         #[diplomat::attr(auto, getter)]
         pub fn magnitude_end(&self) -> i16 {
             *self.0.absolute.magnitude_range().end()
         }
 
-        #[diplomat::rust_link(
-            fixed_decimal::UnsignedFixedDecimal::nonzero_magnitude_start,
-            FnInStruct
-        )]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::nonzero_magnitude_start, FnInStruct)]
         #[diplomat::attr(auto, getter)]
         pub fn nonzero_magnitude_start(&self) -> i16 {
             self.0.absolute.nonzero_magnitude_start()
         }
 
-        #[diplomat::rust_link(
-            fixed_decimal::UnsignedFixedDecimal::nonzero_magnitude_end,
-            FnInStruct
-        )]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::nonzero_magnitude_end, FnInStruct)]
         #[diplomat::attr(auto, getter)]
         pub fn nonzero_magnitude_end(&self) -> i16 {
             self.0.absolute.nonzero_magnitude_end()
         }
 
-        #[diplomat::rust_link(fixed_decimal::UnsignedFixedDecimal::is_zero, FnInStruct)]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::is_zero, FnInStruct)]
         #[diplomat::attr(auto, getter)]
         pub fn is_zero(&self) -> bool {
             self.0.absolute.is_zero()
@@ -279,9 +273,9 @@ pub mod ffi {
             self.0.absolute.trim_end()
         }
 
-        #[diplomat::rust_link(fixed_decimal::UnsignedFixedDecimal::trim_end_if_integer, FnInStruct)]
+        #[diplomat::rust_link(fixed_decimal::UnsignedDecimal::trim_end_if_integer, FnInStruct)]
         #[diplomat::rust_link(
-            fixed_decimal::UnsignedFixedDecimal::trimmed_end_if_integer,
+            fixed_decimal::UnsignedDecimal::trimmed_end_if_integer,
             FnInStruct,
             hidden
         )]

tools/make/diplomat-coverage/src/allowlist.rs

@@ -240,7 +240,7 @@ lazy_static::lazy_static! {
         // Not planned for 2.0
         // We will revisit these APIs when Duration Formatter needs them. We may need to rename things
         "fixed_decimal::Signed",
-        "fixed_decimal::UnsignedFixedDecimal",
+        "fixed_decimal::UnsignedDecimal",
         "fixed_decimal::UnsignedRoundingMode",
 
         // Not planned for 2.0