perf(build): gate .d.ts emission on OS_SKIP_DTS; fix optional AI plugin skip

Part 1 — OS_SKIP_DTS build-time gating (default behavior unchanged):
- 12 tsup configs: dts: true → dts: !process.env.OS_SKIP_DTS
- packages/spec/package.json: skip the separate BUILD_DTS=true tsup pass
  when OS_SKIP_DTS is set (the ~80–90s DTS pass)
- packages/cli/package.json: when OS_SKIP_DTS is set, deps have no .d.ts, so
  build with --noCheck --declaration false to still emit runnable JS
  (full typecheck preserved by default)
- turbo.json: declare OS_SKIP_DTS in globalEnv (Turbo 2.x strict env mode
  otherwise filters it out; also part of the cache key)

Image build (OS_SKIP_DTS=1): framework turbo run build ~5m03s → ~1m12s.

Part 2 — fix optional AI plugin "failed to start" false alarm:
serve.ts loads @objectstack/service-ai and optional @objectstack/service-ai-studio
via importFromHost() and is meant to silently skip when absent. ESM throws
"Cannot find package '...'" (code on err.code, not in message), which the old
guard didn't match, so control-plane hosts logged a scary error on every boot.
Detect missing module via err.code === 'ERR_MODULE_NOT_FOUND' and also match
"Cannot find package". Applied to both the AIService and AIStudio guards.

Refs objectstack-ai/cloud#107

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: os-zhuang

packages/cli/package.json

@@ -9,7 +9,7 @@
     "os": "./bin/run.js"
   },
   "scripts": {
-    "build": "tsc -p tsconfig.build.json",
+    "build": "if [ -n \"$OS_SKIP_DTS\" ]; then tsc -p tsconfig.build.json --noCheck --declaration false --declarationMap false; else tsc -p tsconfig.build.json; fi",
     "dev": "tsc -p tsconfig.build.json --watch",
     "test": "vitest run",
     "lint": "eslint src"

packages/cli/src/commands/serve.ts

@@ -1377,7 +1377,11 @@ export default class Serve extends Command {
           trackPlugin('AIService');
         } catch (err: unknown) {
           const msg = err instanceof Error ? err.message : String(err);
-          if (!msg.includes('Cannot find module') && !msg.includes('ERR_MODULE_NOT_FOUND')) {
+          const code = (err as { code?: string })?.code;
+          const missing = code === 'ERR_MODULE_NOT_FOUND'
+            || msg.includes('Cannot find module')
+            || msg.includes('Cannot find package');
+          if (!missing) {
             console.error('[AI] AIServicePlugin failed to start:', msg);
           }
           // @objectstack/service-ai not installed — AI features unavailable
@@ -1401,7 +1405,11 @@ export default class Serve extends Command {
             trackPlugin('AIStudio');
           } catch (err: unknown) {
             const msg = err instanceof Error ? err.message : String(err);
-            if (!msg.includes('Cannot find module') && !msg.includes('ERR_MODULE_NOT_FOUND')) {
+            const code = (err as { code?: string })?.code;
+            const missing = code === 'ERR_MODULE_NOT_FOUND'
+              || msg.includes('Cannot find module')
+              || msg.includes('Cannot find package');
+            if (!missing) {
               console.error('[AI Studio] AIStudioPlugin failed to start:', msg);
             }
             // @objectstack/service-ai-studio not installed — AI authoring unavailable

packages/cli/tsup.config.ts

@@ -17,7 +17,7 @@ export default defineConfig([
   {
     entry: ['src/index.ts'],
     format: ['esm'],
-    dts: true,
+    dts: !process.env.OS_SKIP_DTS,
     shims: true,
   },
 ]);

packages/core/tsup.config.ts

@@ -13,7 +13,7 @@ export default defineConfig({
   splitting: false,
   sourcemap: true,
   clean: true,
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   format: ['esm', 'cjs'],
   target: 'es2020',
 });

packages/metadata-core/tsup.config.ts

@@ -7,7 +7,7 @@ export default defineConfig({
   splitting: true,
   sourcemap: true,
   clean: true,
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   format: ['esm', 'cjs'],
   target: 'es2020',
   external: ['vitest'],

packages/metadata-fs/tsup.config.ts

@@ -7,7 +7,7 @@ export default defineConfig({
   splitting: false,
   sourcemap: true,
   clean: true,
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   format: ['esm', 'cjs'],
   target: 'es2020',
   external: ['chokidar', '@objectstack/metadata-core'],

packages/metadata/tsup.config.ts

@@ -11,7 +11,7 @@ export default defineConfig({
   splitting: false,
   sourcemap: true,
   clean: true,
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   format: ['esm', 'cjs'],
   target: 'es2020',
 });

packages/platform-objects/tsup.config.ts

@@ -17,7 +17,7 @@ export default defineConfig({
     plugin: 'src/plugin.ts',
   },
   format: ['cjs', 'esm'],
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   clean: true,
   sourcemap: true,
   splitting: false,

packages/plugins/plugin-webhooks/tsup.config.ts

@@ -7,7 +7,7 @@ export default defineConfig({
     splitting: true,
     sourcemap: true,
     clean: true,
-    dts: true,
+    dts: !process.env.OS_SKIP_DTS,
     format: ['esm', 'cjs'],
     target: 'es2020',
     external: ['vitest'],

packages/runtime/tsup.config.ts

@@ -7,7 +7,7 @@ export default defineConfig({
   splitting: false,
   sourcemap: true,
   clean: true,
-  dts: true,
+  dts: !process.env.OS_SKIP_DTS,
   format: ['esm', 'cjs'],
   target: 'es2020',
   // Mark driver packages as external so they are resolved at runtime, not bundled