chore: remove unused build scripts

All packages are pure Bun/TS — no build step needed.
The build scripts were all placeholder `echo 'TODO'` anyway.

package.json

@@ -6,7 +6,6 @@
     "examples"
   ],
   "scripts": {
-    "build": "bun run --filter '*' build",
     "check": "bunx tsc --build && biome check .",
     "typecheck": "bunx tsc --build",
     "format": "biome format --write .",

packages/cli-workflow/package.json

@@ -10,7 +10,6 @@
     "yaml": "^2.8.4"
   },
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   }
 }

packages/workflow-agent-cursor/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow-agent-hermes/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow-agent-llm/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow-template-develop/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow-template-solve-issue/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow-util-agent/package.json

@@ -11,7 +11,6 @@
     }
   },
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {

packages/workflow/package.json

@@ -5,7 +5,6 @@
   "main": "src/index.ts",
   "types": "src/index.ts",
   "scripts": {
-    "build": "echo 'TODO'",
     "test": "bun test"
   },
   "dependencies": {