feat : ABI upgrade from abi_stabby to stabby since abi_stable is no longer maintained (#21030)

## Which issue does this PR close?

<!--
We generally require a GitHub issue to be filed for all bug fixes and
enhancements and this helps us generate change logs for our releases.
You can link an issue to this PR using the GitHub syntax. For example
`Closes #123` indicates that this PR will close issue #123.
-->

- Closes #20863

## Rationale for this change

<!--
Why are you proposing this change? If this is already explained clearly
in the issue then this section is not needed.
Explaining clearly why changes are proposed helps reviewers understand
your changes and offer better suggestions for fixes.
-->

## What changes are included in this PR?

  - Replace abi_stable types with stabby equivalents:
    - `RVec`  -> `stabby::vec::Vec`
    - `RString` -> `stabby::string::String`
- Add custom `FFI_Option` and `FFI_Result` types since we have raw
pointers and self referential pointers which can't implement `IStable`
trait needed for stabby
- Rename `macros: rresult` → `sresult`, `rresult_return `→
`sresult_return`
- Fix library path detection for debug/release builds in the example
loader
  - Update README 

<!--
There is no need to duplicate the description in the issue here but it
is sometimes worth providing a summary of the individual changes in this
PR.
-->

## Are these changes tested?

Yes . With df python bindings on DF 52 release 

<!--
We typically require tests for all PRs in order to:
1. Prevent the code from being accidentally broken by subsequent changes
2. Serve as another way to document the expected behavior of the code

If tests are not included in your PR, please explain why (for example,
are they covered by existing tests)?
-->

## Are there any user-facing changes?

<!--
If there are user-facing changes then we may require documentation to be
updated before approving the PR.
-->

<!--
If there are any breaking changes to public APIs, please add the `api
change` label.
-->

Author: coderfender

Cargo.lock

@@ -22,7 +22,6 @@ edition = { workspace = true }
 publish = false
 
 [dependencies]
-abi_stable = "0.11.3"
 arrow = { workspace = true }
 datafusion = { workspace = true }
 datafusion-ffi = { workspace = true }

datafusion-examples/examples/ffi/ffi_example_table_provider/Cargo.toml

@@ -17,13 +17,12 @@
 
 use std::sync::Arc;
 
-use abi_stable::{export_root_module, prefix_type::PrefixTypeTrait};
 use arrow::array::RecordBatch;
 use arrow::datatypes::{DataType, Field, Schema};
 use datafusion::{common::record_batch, datasource::MemTable};
 use datafusion_ffi::proto::logical_extension_codec::FFI_LogicalExtensionCodec;
 use datafusion_ffi::table_provider::FFI_TableProvider;
-use ffi_module_interface::{TableProviderModule, TableProviderModuleRef};
+use ffi_module_interface::TableProviderModule;
 
 fn create_record_batch(start_value: i32, num_values: usize) -> RecordBatch {
     let end_value = start_value + num_values as i32;
@@ -56,11 +55,10 @@ extern "C" fn construct_simple_table_provider(
     FFI_TableProvider::new_with_ffi_codec(Arc::new(table_provider), true, None, codec)
 }
 
-#[export_root_module]
+#[unsafe(no_mangle)]
 /// This defines the entry point for using the module.
-pub fn get_simple_memory_table() -> TableProviderModuleRef {
+pub extern "C" fn ffi_example_get_module() -> TableProviderModule {
     TableProviderModule {
         create_table: construct_simple_table_provider,
     }
-    .leak_into_prefix()
 }

datafusion-examples/examples/ffi/ffi_example_table_provider/src/lib.rs

@@ -25,5 +25,4 @@ publish = false
 workspace = true
 
 [dependencies]
-abi_stable = "0.11.3"
 datafusion-ffi = { workspace = true }