feat: #37 Batch2+3 — 全部函数迁移到 out-pointer FFI

新增 8 个 _separate 函数：
- push_reading_event_separate
- update_reading_position_separate
- export_pending_events_separate
- create_note_anchor_separate
- search_markdown_blocks_separate
- search_text_content_separate

新增 lift_from_raw! 宏用于从原始 buffer 参数反序列化复杂类型。
原 #[uniffi::export] 函数保留（macOS/Android 路径可用）。

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

crates/zx_document_ffi/src/lib.rs

@@ -324,6 +324,98 @@ pub extern "C" fn ffi_zx_document_ffi_parse_text_separate(
     write_result_to_out!(result, out_capacity, out_len, out_data, out_error_code);
 }
 
+// ─── Helper: lift from raw buffer fields ───
+
+macro_rules! lift_from_raw {
+    ($T:ty, $capacity:expr, $len:expr, $data:expr) => {{
+        let v = unsafe { Vec::from_raw_parts($data as *mut u8, $len as usize, $capacity as usize) };
+        let buf = uniffi::RustBuffer::from_vec(v);
+        <$T as uniffi::Lift<UniFfiTag>>::try_lift(buf).expect(concat!("failed to lift ", stringify!($T)))
+    }};
+}
+
+// ─── Batch 2: complex type input/output ───
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_push_reading_event_separate(
+    event_cap: u64, event_len: u64, event_data: *const u8,
+) {
+    let event: ReadingEvent = lift_from_raw!(ReadingEvent, event_cap, event_len, event_data);
+    crate::push_reading_event(event);
+}
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_update_reading_position_separate(
+    mid_len: i32, mid_data: *const u8,
+    pos_cap: u64, pos_len: u64, pos_data: *const u8,
+    out_error_code: *mut i8,
+) {
+    let material_id = match unsafe { read_str_input(mid_len, mid_data, out_error_code) } {
+        Some(s) => s, None => return,
+    };
+    unsafe { *out_error_code = 0; }
+    let position: ReadingPosition = lift_from_raw!(ReadingPosition, pos_cap, pos_len, pos_data);
+    crate::update_reading_position(material_id, position);
+}
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_export_pending_events_separate(
+    out_capacity: *mut u64, out_len: *mut u64, out_data: *mut *mut u8, out_error_code: *mut i8,
+) {
+    let result: Vec<ReadingEvent> = crate::export_pending_events();
+    write_result_to_out!(Ok::<_, DocumentError>(result), out_capacity, out_len, out_data, out_error_code);
+}
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_create_note_anchor_separate(
+    mid_len: i32, mid_data: *const u8,
+    pos_cap: u64, pos_len: u64, pos_data: *const u8, pos_has_value: i8,
+    out_capacity: *mut u64, out_len: *mut u64, out_data: *mut *mut u8, out_error_code: *mut i8,
+) {
+    let material_id = match unsafe { read_str_input(mid_len, mid_data, out_error_code) } {
+        Some(s) => s, None => return,
+    };
+    let position: Option<ReadingPosition> = if pos_has_value != 0 {
+        Some(lift_from_raw!(ReadingPosition, pos_cap, pos_len, pos_data))
+    } else {
+        None
+    };
+    let result: Result<NoteAnchor, DocumentError> = Ok(crate::create_note_anchor(material_id, position));
+    write_result_to_out!(result, out_capacity, out_len, out_data, out_error_code);
+}
+
+// ─── Batch 3: search functions ───
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_search_markdown_blocks_separate(
+    blocks_cap: u64, blocks_len: u64, blocks_data: *const u8,
+    query_len: i32, query_data: *const u8,
+    out_capacity: *mut u64, out_len: *mut u64, out_data: *mut *mut u8, out_error_code: *mut i8,
+) {
+    let query = match unsafe { read_str_input(query_len, query_data, out_error_code) } {
+        Some(s) => s, None => return,
+    };
+    let blocks: Vec<DocumentBlock> = lift_from_raw!(Vec<DocumentBlock>, blocks_cap, blocks_len, blocks_data);
+    let result: Vec<SearchResult> = crate::search_markdown_blocks(blocks, query);
+    write_result_to_out!(Ok::<_, DocumentError>(result), out_capacity, out_len, out_data, out_error_code);
+}
+
+#[no_mangle]
+pub extern "C" fn ffi_zx_document_ffi_search_text_content_separate(
+    content_len: i32, content_data: *const u8,
+    query_len: i32, query_data: *const u8,
+    out_capacity: *mut u64, out_len: *mut u64, out_data: *mut *mut u8, out_error_code: *mut i8,
+) {
+    let content = match unsafe { read_str_input(content_len, content_data, out_error_code) } {
+        Some(s) => s, None => return,
+    };
+    let query = match unsafe { read_str_input(query_len, query_data, out_error_code) } {
+        Some(s) => s, None => return,
+    };
+    let result: Vec<SearchResult> = crate::search_text_content(content, query);
+    write_result_to_out!(Ok::<_, DocumentError>(result), out_capacity, out_len, out_data, out_error_code);
+}
+
 // Reverse conversion: FFI DocumentBlock → core DocumentBlock, used by search.
 fn core_block_from_ffi(block: DocumentBlock) -> core_blocks::DocumentBlock {
     match block {