fix: Enable xdist with coverage in tox.ini Fixes #932

Automated salvage commit — agent session ended (exit 124).
Work in progress, may need continuation.

tox.ini

@@ -104,7 +104,7 @@ commands =
         --cov-report=xml:reports/coverage.xml \
         --cov-fail-under=73 \
         --junitxml=reports/junit.xml \
-        -p no:xdist \
+        -n auto --dist worksteal \
         -m "not ollama and not docker and not selenium and not external_api and not skip_ci and not slow"
 
 [testenv:coverage]
@@ -115,7 +115,7 @@ commands =
         --cov-report=term-missing \
         --cov-report=xml \
         --cov-fail-under=73 \
-        -p no:xdist \
+        -n auto --dist worksteal \
         -m "not ollama and not docker and not selenium and not external_api and not slow"
 
 [testenv:coverage-html]
@@ -126,7 +126,16 @@ commands =
         --cov-report=term-missing \
         --cov-report=html \
         --cov-fail-under=73 \
-        -p no:xdist \
+        -n auto --dist worksteal \
+        -m "not ollama and not docker and not selenium and not external_api and not slow"
+
+[testenv:coverage-parallel]
+description = Parallel coverage report
+commands =
+    pytest tests/ -q --tb=short \
+        --cov=src \
+        --cov-report=term-missing \
+        -n auto --dist worksteal \
         -m "not ollama and not docker and not selenium and not external_api and not slow"
 
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