chore(iast): rename native classes and methods (#14497)

This PR is part of the ongoing [IAST context
refactor](#14466), and
focuses on improving the **naming clarity** of internal structures and
functions used within the IAST subsystem.

### 🔄 What’s changed?

* Renamed several classes and functions to more accurately reflect their
role in the taint tracking lifecycle.
* Renamed TaintRangeMapType → TaintedObjectMapType. Consumers of this
map retrieve a tainted object first, and then access the ranges inside
it. This rename clarifies that the value is the tainted object as a
whole, not just range metadata.
* Renamed get_taint_map  →  get_tainted_object_map
* Replaced previously confusing or ambiguous terms with consistent,
descriptive alternatives (e.g., `contexts_array` →
`request_context_slots`, `ApplicationContext` -> `TaintEngineContext`,
etc.).


### 🧠 Why?

The current naming was either overly generic or misleading, making the
IAST implementation harder to understand and maintain. This refactor
aligns terminology with:
```
Application Request
├── start_request_context()
│   ├── Acquire slot from request_context_slots (max 2)
│   ├── Get a new request_context_slots
│   │   └── Initialize TaintedObjectMap (e.g., empty dict keyed by id(obj))
│   └── Register context into ApplicationContext.context_slots[n]
│
├── Propagation phase
│   ├── get_tainted_object_map() → Retrieve current TaintedObjectMap from TaintEngineContext.request_context_slots
│   ├── Check if object is tainted via id(obj) in map
│   └── If needed, update/add TaintRanges to TaintedObject in TaintedObjectMap
│
└── finish_request_context()
    ├── Clear TaintedObjectMap (remove all taint metadata for the request)
    └── Release slot in TaintEngineContext.request_context_slots (allow new request to reuse)
```


## Checklist
- [x] PR author has checked that all the criteria below are met
- The PR description includes an overview of the change
- The PR description articulates the motivation for the change
- The change includes tests OR the PR description describes a testing
strategy
- The PR description notes risks associated with the change, if any
- Newly-added code is easy to change
- The change follows the [library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
- The change includes or references documentation updates if necessary
- Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist
- [x] Reviewer has checked that all the criteria below are met 
- Title is accurate
- All changes are related to the pull request's stated goal
- Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes
- Testing strategy adequately addresses listed risks
- Newly-added code is easy to change
- Release note makes sense to a user of the library
- If necessary, author has acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment
- Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)

Author: avara1986

ddtrace/appsec/_iast/_taint_tracking/__init__.py

@@ -18,7 +18,7 @@
 from ddtrace.appsec._iast._taint_tracking._native.aspects_ospath import _aspect_ospathsplitdrive  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.aspects_ospath import _aspect_ospathsplitext  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.aspects_ospath import _aspect_ospathsplitroot  # noqa: F401
-from ddtrace.appsec._iast._taint_tracking._native.context import get_taint_map  # noqa: F401
+from ddtrace.appsec._iast._taint_tracking._native.context import is_in_taint_map  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.initializer import active_map_addreses_size  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.initializer import debug_taint_map  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.initializer import num_objects_tainted  # noqa: F401
@@ -73,7 +73,7 @@
     "debug_taint_map",
     "get_range_by_hash",
     "get_ranges",
-    "get_taint_map",
+    "is_in_taint_map",
     "is_tainted",
     "new_pyobject_id",
     "num_objects_tainted",

ddtrace/appsec/_iast/_taint_tracking/_context.py

@@ -1,9 +1,13 @@
+from ddtrace.appsec._iast._taint_tracking._native.context import finish_request_context
+from ddtrace.appsec._iast._taint_tracking._native.context import start_request_context
 from ddtrace.appsec._iast._taint_tracking._native.initializer import create_context  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.initializer import reset_context  # noqa: F401
 from ddtrace.appsec._iast._taint_tracking._native.initializer import reset_contexts  # noqa: F401
 
 
 __all__ = [
+    "start_request_context",
+    "finish_request_context",
     "create_context",
     "reset_context",
     "reset_contexts",

ddtrace/appsec/_iast/_taint_tracking/_taint_objects_base.py

@@ -6,7 +6,7 @@
 from ddtrace.appsec._iast._logs import iast_propagation_error_log
 from ddtrace.appsec._iast._taint_tracking import OriginType
 from ddtrace.appsec._iast._taint_tracking import get_ranges
-from ddtrace.appsec._iast._taint_tracking import get_taint_map
+from ddtrace.appsec._iast._taint_tracking import is_in_taint_map
 from ddtrace.appsec._iast._taint_tracking import is_tainted
 from ddtrace.appsec._iast._taint_tracking import origin_to_str
 from ddtrace.appsec._iast._taint_tracking import set_ranges
@@ -149,7 +149,7 @@ def is_pyobject_tainted_new(pyobject: Any) -> bool:
         return False
 
     try:
-        return get_taint_map(pyobject)
+        return is_in_taint_map(pyobject)
     except ValueError as e:
         iast_propagation_error_log(f"Checking tainted object error: {e}")
     return False

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_index.cpp

@@ -17,7 +17,7 @@ index_aspect(PyObject* result_o,
              const PyObject* candidate_text,
              PyObject* idx,
              const TaintRangeRefs& ranges,
-             const TaintRangeMapTypePtr& tx_map)
+             const TaintedObjectMapTypePtr& tx_map)
 {
     TaintRangeRefs ranges_to_set;
 

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_index.h

@@ -6,6 +6,6 @@ index_aspect(PyObject* result_o,
              const PyObject* candidate_text,
              PyObject* idx,
              const TaintRangeRefs& ranges,
-             const TaintRangeMapTypePtr& tx_taint_map);
+             const TaintedObjectMapTypePtr& tx_taint_map);
 PyObject*
 api_index_aspect(PyObject* self, PyObject* const* args, Py_ssize_t nargs);

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_join.cpp

@@ -7,7 +7,7 @@ aspect_join_str(PyObject* sep,
                 PyObject* result,
                 PyObject* iterable_str,
                 size_t len_iterable,
-                const TaintRangeMapTypePtr& tx_taint_map)
+                const TaintedObjectMapTypePtr& tx_taint_map)
 {
     // This is the special case for unicode str and unicode iterable_str.
     // The iterable elements string will be split into 1 char-length strings.
@@ -60,7 +60,7 @@ aspect_join_str(PyObject* sep,
 }
 
 PyObject*
-aspect_join(PyObject* sep, PyObject* result, PyObject* iterable_elements, const TaintRangeMapTypePtr& tx_taint_map)
+aspect_join(PyObject* sep, PyObject* result, PyObject* iterable_elements, const TaintedObjectMapTypePtr& tx_taint_map)
 {
     const size_t& len_sep = get_pyobject_size(sep);
 

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_operator_add.cpp

@@ -15,7 +15,7 @@ PyObject*
 add_aspect(PyObject* result_o,
            PyObject* candidate_text,
            PyObject* text_to_add,
-           const TaintRangeMapTypePtr& tx_taint_map)
+           const TaintedObjectMapTypePtr& tx_taint_map)
 {
     const size_t len_candidate_text{ get_pyobject_size(candidate_text) };
     const size_t len_text_to_add{ get_pyobject_size(text_to_add) };

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_split.cpp

@@ -6,7 +6,7 @@ static std::optional<py::object>
 handle_potential_re_split(const py::tuple& args,
                           const py::tuple& sliced_args,
                           const py::kwargs& kwargs,
-                          const TaintRangeMapTypePtr& tx_map)
+                          const TaintedObjectMapTypePtr& tx_map)
 {
     const py::module re = py::module::import("re");
     const py::object re_pattern_type = re.attr("Pattern");

ddtrace/appsec/_iast/_taint_tracking/aspects/aspect_str.cpp

@@ -5,7 +5,7 @@ static void
 set_lengthupdated_ranges(PyObject* result,
                          Py_ssize_t result_len,
                          const TaintRangeRefs& ranges,
-                         const TaintRangeMapTypePtr& tx_map)
+                         const TaintedObjectMapTypePtr& tx_map)
 {
     if (!tx_map || tx_map->empty()) {
         return;

ddtrace/appsec/_iast/_taint_tracking/aspects/helpers.cpp

@@ -299,7 +299,7 @@ bool
 set_ranges_on_splitted(const py::object& source_str,
                        const TaintRangeRefs& source_ranges,
                        const py::list& split_result,
-                       const TaintRangeMapTypePtr& tx_map,
+                       const TaintedObjectMapTypePtr& tx_map,
                        bool include_separator)
 {
     RANGE_START offset = 0;