test(code-mappings): Add test for HTTP 207 partial success response

Verify the CLI correctly handles HTTP 207 Multi-Status responses from the
bulk code-mappings endpoint. The CLI treats 207 as a success at the HTTP
level and relies on the JSON body to surface per-mapping errors.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: romtsn

tests/integration/_cases/code_mappings/code-mappings-upload-207-partial-error.trycmd

@@ -0,0 +1,17 @@
+```
+$ sentry-cli code-mappings upload tests/integration/_fixtures/code_mappings/mappings.json --org wat-org --project wat-project --repo owner/repo --default-branch main
+? failed
+Uploading 2 code mapping(s)...
++------------------+---------------------------------------------+-------------------+
+| Stack Root       | Source Root                                 | Detail            |
++------------------+---------------------------------------------+-------------------+
+| com/example/maps | modules/maps/src/main/java/com/example/maps | duplicate mapping |
++------------------+---------------------------------------------+-------------------+
+
+Created: 1, Updated: 0, Errors: 1
+error: 1 error(s) during upload. See details above.
+
+Add --log-level=[info|debug] or export SENTRY_LOG_LEVEL=[info|debug] to see more output.
+Please attach the full debug log to all bug reports.
+
+```

tests/integration/_responses/code_mappings/post-bulk-207-partial-error.json

@@ -0,0 +1,9 @@
+{
+  "created": 1,
+  "updated": 0,
+  "errors": 1,
+  "mappings": [
+    {"stackRoot": "com/example/core", "sourceRoot": "modules/core/src/main/java/com/example/core", "status": "created"},
+    {"stackRoot": "com/example/maps", "sourceRoot": "modules/maps/src/main/java/com/example/maps", "status": "error", "detail": "duplicate mapping"}
+  ]
+}

tests/integration/code_mappings/upload.rs

@@ -24,6 +24,18 @@ fn command_code_mappings_upload_partial_error() {
         .with_default_token();
 }
 
+#[test]
+fn command_code_mappings_upload_207_partial_error() {
+    TestManager::new()
+        .mock_endpoint(
+            MockEndpointBuilder::new("POST", "/api/0/organizations/wat-org/code-mappings/bulk/")
+                .with_status(207)
+                .with_response_file("code_mappings/post-bulk-207-partial-error.json"),
+        )
+        .register_trycmd_test("code_mappings/code-mappings-upload-207-partial-error.trycmd")
+        .with_default_token();
+}
+
 #[test]
 fn command_code_mappings_upload_batches() {
     // Generate a fixture with 301 mappings to force 2 batches (300 + 1).