Added Cap::DATA_EXFIL and taint fp and fn fixes on real repos (#59)

* feat: Enhance data exfiltration detection with source sensitivity gating for cookies and headers

* feat: Implement cross-file data exfiltration detection with parameter-specific gate filters

* feat: Add calibration tests and refine DATA_EXFIL severity scoring logic

* feat: Introduce per-detector configuration for data exfiltration suppression

* feat: Enhance DATA_EXFIL findings with destination field tracking in diagnostics and SARIF output

* feat: Add tainted body and URL handling for data exfiltration detection

* feat: Add integration tests and fixtures for DATA_EXFIL and SSRF detection in Go

* feat: Add Java integration tests and fixtures for DATA_EXFIL detection across multiple HTTP clients

* feat: Add synthetic externals handling for closure-captured variables in SSA

* feat: Implement closure-based suppression for resource leak findings

* feat: Add regression guards for shell-injection and taint propagation in for-of destructure patterns

* feat: Implement constructor cap narrowing for data exfiltration detection in HTTP request builders

* feat: Add gated sinks for data exfiltration detection in C and C++ using curl_easy_setopt

* feat: Implement DATA_EXFIL cap parity for backwards analysis and add integration tests

* feat: Add data exfiltration sinks for various languages and enhance documentation

* refactor: Simplify formatting and improve readability in various files

* refactor: Improve readability by simplifying conditional statements and adding clippy linting

* docs: Update CHANGELOG and comments for data exfiltration features and configuration

* docs: Clarify configuration instructions for data exfiltration trusted destinations

* docs: Enhance comments for evidence routing logic in data exfiltration

tests/cross_file_data_exfil_split_tests.rs

@@ -0,0 +1,48 @@
+//! Integration test for cross-file `param_to_gate_filters` propagation.
+//!
+//! A wrapper function whose two parameters target distinct gated-sink
+//! classes on a single inner call (here, `fetch`'s SSRF gate on the URL
+//! arg vs the DATA_EXFIL gate on the body arg) must keep cap attribution
+//! per-position when callers reach it across a file boundary.  Without
+//! [`SsaFuncSummary::param_to_gate_filters`], the wrapper's summary
+//! collapses both params into a single `SSRF | DATA_EXFIL` mask, and
+//! every caller incorrectly fires both classes regardless of which
+//! argument was tainted.
+//!
+//! The fixture pairs the wrapper with two callers, each tainting one
+//! parameter and asserting only the cap class corresponding to that
+//! parameter's gate fires.
+
+mod common;
+
+use common::{scan_fixture_dir, validate_expectations};
+use nyx_scanner::utils::config::AnalysisMode;
+use std::path::{Path, PathBuf};
+
+fn fixture_path(name: &str) -> PathBuf {
+    Path::new(env!("CARGO_MANIFEST_DIR"))
+        .join("tests")
+        .join("fixtures")
+        .join(name)
+}
+
+#[test]
+fn cross_file_data_exfil_split() {
+    let dir = fixture_path("cross_file_data_exfil_split");
+    let diags = scan_fixture_dir(&dir, AnalysisMode::Full);
+    validate_expectations(&diags, &dir);
+}
+
+/// Python parallel of the JS cross-file split fixture.  A wrapper
+/// `forward(url, body)` calls `requests.post(url, json=body)` so the URL
+/// flows to the SSRF gate and the body kwarg flows to the DATA_EXFIL
+/// gate.  Per-position cap attribution must hold across the file
+/// boundary: a caller that taints only the URL fires SSRF (no
+/// DATA_EXFIL), and a caller that taints only the body with a Sensitive
+/// source fires DATA_EXFIL (no SSRF).
+#[test]
+fn cross_file_python_data_exfil() {
+    let dir = fixture_path("cross_file_python_data_exfil");
+    let diags = scan_fixture_dir(&dir, AnalysisMode::Full);
+    validate_expectations(&diags, &dir);
+}