feat: add build system, stubs, and npm packaging — openclaude is now runnable

- package.json with all 70+ dependencies
- Bun build script with feature flag shims, native module stubs, otel externals
- Stubs for ~15 missing source files (snapshot gaps)
- tsconfig.json for TypeScript
- bin/openclaude entry point
- Builds to single 19MB dist/cli.mjs
- Verified: --version and --help work

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/utils/filePersistence/types.ts

@@ -0,0 +1,13 @@
+// Stub — types not included in source snapshot
+export const OUTPUTS_SUBDIR = 'tool-results'
+
+export interface PersistedFile {
+  path: string
+  content: string
+  size: number
+}
+
+export type TurnStartTime = number
+
+export const DEFAULT_UPLOAD_CONCURRENCY = 5
+export const FILE_COUNT_LIMIT = 100

src/utils/protectedNamespace.ts

@@ -0,0 +1,3 @@
+// Stub
+export function isProtectedNamespace(_ns: string): boolean { return false }
+export const PROTECTED_NAMESPACES: string[] = []

src/utils/ultraplan/prompt.txt

@@ -0,0 +1 @@
+This is a planning prompt stub.