feat(reasoning-effort): persisted per-conversation + per-turn override, threaded to providers

- conversation-store: get/setReasoningEffort (own key space, mirrors cwd)
- session-orchestrator: resolveReasoningEffort (override -> stored -> 'high'),
  StartTurnInput.reasoningEffort, warm() parity (cache-safe)
- transport-http: /chat validation (400 on bad level) + GET/PUT
  /conversations/:id/reasoning-effort
- transport-ws: chat.send threading + validation
- cli: --effort <low|medium|high|xhigh|max>

993 vitest + 189 bun tests green; typecheck + biome clean.

1 files changed, 3 insertions, 1 deletions

diff --git a/packages/cli/src/message.ts b/packages/cli/src/message.ts
index 0c3f538..80befec 100644
--- a/packages/cli/src/message.ts
+++ b/packages/cli/src/message.ts
@@ -5,7 +5,7 @@
  * and builds a ChatRequest from a parsed command.
  */
 
-import type { ChatRequest } from "@dispatch/transport-contract";
+import type { ChatRequest, ReasoningEffort } from "@dispatch/transport-contract";
 
 interface ComposeInput {
 	readonly text?: string;
@@ -37,6 +37,7 @@ interface ChatCmd {
 	readonly file?: string | undefined;
 	readonly cwd?: string | undefined;
 	readonly conversationId?: string | undefined;
+	readonly reasoningEffort?: ReasoningEffort | undefined;
 	readonly showReasoning: boolean;
 }
 
@@ -51,5 +52,6 @@ export function buildChatRequest(cmd: ChatCmd, ctx: BuildCtx): ChatRequest {
 		model: cmd.modelName,
 		...(cmd.conversationId !== undefined && { conversationId: cmd.conversationId }),
 		...(cmd.cwd !== undefined ? { cwd: cmd.cwd } : { cwd: ctx.cwd }),
+		...(cmd.reasoningEffort !== undefined && { reasoningEffort: cmd.reasoningEffort }),
 	};
 }