feat(parse_size): Add comprehensive builder validation to prevent fragile configurations

Addresses PR uutils#9653 review feedback about 'fragile commands' by implementing
fail-fast validation in Parser builder pattern.

Changes:
- Add ParserBuilderError enum with 8 validation error variants
- Refactor builder methods to return Result<&mut Self, ParserBuilderError>
- Implement comprehensive unit validation (57 valid units including k/m/g/t)
- Add cross-validation between builder settings (default_unit vs allow_list)
- Detect conflicts (b_byte_count with 'b' unit, '%' with size units)
- Update all call sites (sort, du, df, od) to handle new error types
- Fix invalid '%' unit in sort's parse_byte_count allow_list

Benefits:
- Configuration errors detected immediately (not during parsing)
- Clear error messages listing invalid/conflicting settings
- Maintains backward compatibility through explicit error reporting

Files modified:
- src/uucore/src/lib/features/parser/parse_size.rs (core implementation)
- src/uu/sort/src/sort.rs (error handling + fix invalid '%')
- src/uu/du/src/du.rs (error handling)
- src/uu/df/src/df.rs (error handling)
- src/uu/od/src/od.rs (error handling)

Author: naoNao89

src/uu/df/src/df.rs

@@ -167,6 +167,7 @@ impl Options {
                 ),
                 ParseSizeError::ParseFailure(s) => OptionsError::InvalidBlockSize(s),
                 ParseSizeError::PhysicalMem(s) => OptionsError::InvalidBlockSize(s),
+                ParseSizeError::BuilderConfig(e) => OptionsError::InvalidBlockSize(e.to_string()),
             })?,
             header_mode: {
                 if matches.get_flag(OPT_HUMAN_READABLE_BINARY)

src/uu/du/src/du.rs

@@ -1490,6 +1490,9 @@ fn format_error_message(error: &ParseSizeError, s: &str, option: &str) -> String
         ParseSizeError::SizeTooBig(_) => {
             translate!("du-error-argument-too-large", "option" => option, "value" => s.quote())
         }
+        ParseSizeError::BuilderConfig(e) => {
+            format!("invalid configuration for {option}: {e}")
+        }
     }
 }
 

src/uu/od/src/od.rs

@@ -804,5 +804,8 @@ fn format_error_message(error: &ParseSizeError, s: &str, option: &str) -> String
         ParseSizeError::SizeTooBig(_) => {
             translate!("od-error-argument-too-large", "option" => option, "value" => s.quote())
         }
+        ParseSizeError::BuilderConfig(e) => {
+            format!("invalid configuration for {option}: {e}")
+        }
     }
 }

src/uu/sort/src/sort.rs

@@ -319,10 +319,10 @@ impl GlobalSettings {
         // GNU sort (8.32) invalid:  b, B, 1B,                         p, e, z, y
         let size = Parser::default()
             .with_allow_list(&[
-                "b", "k", "K", "m", "M", "g", "G", "t", "T", "P", "E", "Z", "Y", "R", "Q", "%",
-            ])
-            .with_default_unit("K")
-            .with_b_byte_count(true)
+                "b", "k", "K", "m", "M", "g", "G", "t", "T", "P", "E", "Z", "Y", "R", "Q",
+            ])?
+            .with_default_unit("K")?
+            .with_b_byte_count(true)?
             .parse(input.trim())?;
 
         usize::try_from(size).map_err(|_| {
@@ -2268,6 +2268,9 @@ fn format_error_message(error: &ParseSizeError, s: &str, option: &str) -> String
         ParseSizeError::SizeTooBig(_) => {
             translate!("sort-option-arg-too-large", "option" => option, "arg" => s.quote())
         }
+        ParseSizeError::BuilderConfig(e) => {
+            format!("invalid configuration for {option}: {e}")
+        }
     }
 }