Improve CLI error handling for contract invocation arguments (#2235)

Fixes #2182 - Enhanced error messages with context and suggestions for
better developer experience when invoking contracts, especially with
bash scripts.
Providing detailed, context-rich error messages for contract invocation
arguments, including expected vs. received types and actionable
suggestions.

- Pre-validating JSON arguments to catch malformed input and type
mismatches early.
- Detecting common mistakes, such as invalid addresses and quoting
errors, with documentation links and best practices.
- Refactoring argument parsing internals for better organization,
maintainability, and adherence to Rust best practices:
- Extracts long functions into focused helpers (build_clap_command,
parse_command_matches, get_function_spec, parse_function_arguments,
parse_single_argument, parse_file_argument, build_invoke_contract_args).
- Improves error handling (e.g., replacing map().unwrap_or_else() with
explicit matching).

### Example improvement:
**Before**: Error: parsing argument amount: InvalidValue(Some(U64)) 
**After**: Failed to parse argument 'amount' - Expected u64 but received
'"100"'
       Suggestion: For numbers, ensure no quotes around the value

---------

Co-authored-by: Nando Vieira <me@fnando.com>

Author: sagpatil

cmd/crates/soroban-test/tests/it/help.rs

@@ -62,7 +62,7 @@ async fn complex_enum_help() {
 async fn multi_arg_failure() {
     assert!(matches!(
         invoke_custom("multi_args", "--b").await.unwrap_err(),
-        contract::invoke::Error::ArgParsing(arg_parsing::Error::MissingArgument(_))
+        contract::invoke::Error::ArgParsing(arg_parsing::Error::MissingArgument { .. })
     ));
 }