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/coder/src/services/provider-snapshot.ts

@@ -29,6 +29,22 @@ interface AgentRow {
   last_probed_at: string | Date | null;
 }
 
+export async function fetchDeepSeekModels(config: Config): Promise<ProviderModel[]> {
+  if (!config.DEEPSEEK_API_KEY) return [];
+  try {
+    const baseURL = (config.DEEPSEEK_BASE_URL ?? 'https://api.deepseek.com').replace(/\/+$/, '');
+    const res = await fetch(`${baseURL}/v1/models`, {
+      headers: { Authorization: `Bearer ${config.DEEPSEEK_API_KEY}` },
+      signal: AbortSignal.timeout(5_000),
+    });
+    if (!res.ok) return [];
+    const parsed = (await res.json()) as { data?: Array<{ id: string }> };
+    return (parsed.data ?? []).map((m) => ({ id: m.id, label: m.id }));
+  } catch {
+    return [];
+  }
+}
+
 export async function fetchLlamaSwapModels(config: Config): Promise<ProviderModel[]> {
   try {
     const res = await fetch(`${config.LLAMA_SWAP_URL}/v1/models`);
@@ -256,7 +272,13 @@ export async function getProviderSnapshot(
   }
 
   const build = async (): Promise<ProviderSnapshotEntry[]> => {
-    const llamaModels = await fetchLlamaSwapModels(config);
+    const [llamaModels, deepseekModels] = await Promise.all([
+      fetchLlamaSwapModels(config),
+      fetchDeepSeekModels(config),
+    ]);
+    // Merge DeepSeek models into the llama-swap model pool so the boocode
+    // provider (which sources from llama-swap) also includes DeepSeek models.
+    const mergedModels = mergeModels(llamaModels, deepseekModels);
     const agents = await sql<AgentRow[]>`
       SELECT name, install_path, supports_acp, models, commands, label, transport, last_probed_at FROM available_agents
     `;
@@ -265,7 +287,7 @@ export async function getProviderSnapshot(
 
     const entries = await Promise.all(
       [...getResolvedRegistry().values()].map((resolved) =>
-        buildProviderEntry(resolved, agentMap.get(resolved.id), llamaModels, resolvedCwd, ttlMs, force),
+        buildProviderEntry(resolved, agentMap.get(resolved.id), mergedModels, resolvedCwd, ttlMs, force),
       ),
     );