Add explicit LLM concurrency controls

README.md

@@ -121,7 +121,6 @@ Environment:
 - `AUDITA_BASE_URL`
 - `AUDITA_LLM_TIMEOUT_SECONDS`
 - `AUDITA_MAX_RETRIES`
-- `AUDITA_LLM_CONCURRENCY`
 
 CLI:
 - `--llm-api-key`
@@ -129,7 +128,6 @@ CLI:
 - `--base-url`
 - `--llm-timeout-seconds`
 - `--max-retries`
-- `--llm-concurrency`
 
 ### Validation LLM
 
@@ -151,9 +149,26 @@ CLI:
 - `--validation-llm-concurrency`
 - `--validation-max-prompt-tokens`
 
-Validation concurrency behavior:
-- when validation concurrency is unset, it inherits primary `llm-concurrency`
-- when explicitly set, validation concurrency must be `<= llm-concurrency`
+### LLM Concurrency
+
+Environment:
+- `AUDITA_TOTAL_LLM_CONCURRENCY`
+- `AUDITA_PROPOSAL_LLM_CONCURRENCY`
+- `AUDITA_VALIDATION_LLM_CONCURRENCY`
+- `AUDITA_LLM_CONCURRENCY` (legacy alias for `AUDITA_TOTAL_LLM_CONCURRENCY`)
+
+CLI:
+- `--total-llm-concurrency`
+- `--proposal-llm-concurrency`
+- `--validation-llm-concurrency`
+- `--llm-concurrency` (legacy alias for `--total-llm-concurrency`)
+
+Behavior:
+- all proposal and validation LLM calls are bounded by total LLM concurrency
+- proposal LLM calls are additionally bounded by proposal LLM concurrency
+- when validation concurrency is unset, it inherits total LLM concurrency
+- when explicitly set, proposal and validation concurrency must each be `<= total-llm-concurrency`
+- canonical total settings win when both canonical and legacy alias settings are provided at the same precedence layer
 
 ### Confidence Thresholds