feat: DeepSeek API integration + Whale lift (hooks, tool repair, MCP permissions, token tracking)

DeepSeek API:
- @ai-sdk/deepseek provider replaces openai-compatible for deepseek-* models
- Token tracking: cache_hit/reasoning tokens flow API → DB → WS frames → UI
- thinking effort levels (off/low/medium/high/xhigh/max) via AGENTS.md frontmatter
- V4 models: deepseek-v4-flash, deepseek-v4-pro
- Wired for both chat and coder panes

Whale lifts:
- Tool input repair (schema-based type coercion, markdown link unwrapping)
- Hooks system (6 lifecycle events, shell exec, JSON stdin/stdout contract)
- Per-MCP-server permissions (allow/ask/deny)
- token tracking UI (cache N, think N in message stats line)

Infra:
- New DB columns: messages.cache_tokens, messages.reasoning_tokens
- New WS frame fields: cache_tokens, reasoning_tokens on message_complete
- coder provider snapshot merges DeepSeek models alongside llama-swap

apps/server/src/services/inference/error-handler.ts

@@ -122,6 +122,8 @@ export async function finalizeStreamedRow(
     completionTokens: number | null;
     promptTokens: number | null;
     startedAt: string | null;
+    cacheTokens?: number | null;
+    reasoningTokens?: number | null;
     beforeComplete?: () => Promise<void>;
   },
 ): Promise<void> {
@@ -137,6 +139,8 @@ export async function finalizeStreamedRow(
         tokens_used = ${opts.completionTokens},
         ctx_used = ${opts.promptTokens},
         ctx_max = ${nCtx},
+        cache_tokens = ${opts.cacheTokens ?? null},
+        reasoning_tokens = ${opts.reasoningTokens ?? null},
         finished_at = clock_timestamp()
     WHERE id = ${opts.messageId}
     RETURNING tokens_used, ctx_used, ctx_max, finished_at
@@ -149,6 +153,8 @@ export async function finalizeStreamedRow(
     tokens_used: updated?.tokens_used ?? null,
     ctx_used: updated?.ctx_used ?? null,
     ctx_max: updated?.ctx_max ?? null,
+    cache_tokens: opts.cacheTokens ?? null,
+    reasoning_tokens: opts.reasoningTokens ?? null,
     started_at: opts.startedAt,
     finished_at: updated?.finished_at ?? null,
     model: opts.model,
@@ -188,7 +194,7 @@ export async function finalizeCompletion(
 ): Promise<void> {
   const { sessionId, chatId, assistantMessageId } = args;
   const content = stripToolMarkup(result.content, { final: true });
-  const { finishReason, promptTokens, completionTokens } = result;
+  const { finishReason, promptTokens, completionTokens, cacheReadTokens, reasoningTokens } = result;
 
   // v1.11.3: see executeToolPhase for the rationale.
   const mctx = await modelContext.getModelContext(session.model);
@@ -203,6 +209,8 @@ export async function finalizeCompletion(
         tokens_used = ${completionTokens},
         ctx_used = ${promptTokens},
         ctx_max = ${nCtx},
+        cache_tokens = ${cacheReadTokens ?? null},
+        reasoning_tokens = ${reasoningTokens ?? null},
         model = ${session.model},
         finished_at = clock_timestamp()
     WHERE id = ${assistantMessageId}
@@ -268,6 +276,8 @@ export async function finalizeCompletion(
     tokens_used: updated?.tokens_used ?? null,
     ctx_used: updated?.ctx_used ?? null,
     ctx_max: updated?.ctx_max ?? null,
+    cache_tokens: cacheReadTokens ?? null,
+    reasoning_tokens: reasoningTokens ?? null,
     started_at: startedAt,
     finished_at: updated?.finished_at ?? null,
     model: session.model,