feat: add searxng web-search provider, openrouter cost balance UI, offline scripts; update source-launch and docs

scripts/run-source-dsh.ts

@@ -0,0 +1,65 @@
+#!/usr/bin/env node
+/**
+ * Source `pnpm dsh` entry: overlay a checkout-local HTTP proxy, respawn this
+ * Node process so `fetch` binds it at start, then dispatch the CLI. The
+ * calling shell is unchanged.
+ * @module
+ */
+
+/* v8 ignore file -- overlay behavior is tested in apply-source-dsh-http-proxy.spec.ts. */
+
+import { spawn } from 'node:child_process'
+import {
+  applySourceDshHttpProxy,
+  readSourceDshHttpProxyFile,
+  shouldReexecSourceDshForFetchProxy,
+  SOURCE_DSH_PROXY_REEXEC_MARKER,
+  sourceDshAppliedHttpProxyUrl,
+  sourceDshHttpProxyOverlayPresent,
+} from './apply-source-dsh-http-proxy.ts'
+
+const fileText = readSourceDshHttpProxyFile()
+const overlayUrl = process.env.DSH_HTTP_PROXY
+try {
+  applySourceDshHttpProxy({
+    env: process.env,
+    fileText,
+    overlayUrl,
+  })
+} catch (error) {
+  const message = error instanceof Error ? error.message : String(error)
+  process.stderr.write(`dsh: ${message}\n`)
+  process.exit(1)
+}
+
+const appliedProxy = sourceDshAppliedHttpProxyUrl(process.env)
+if (
+  appliedProxy !== undefined
+  && process.env[SOURCE_DSH_PROXY_REEXEC_MARKER] !== '1'
+) {
+  process.stderr.write(`dsh: HTTP proxy overlay ${appliedProxy} (this Node process only)\n`)
+}
+
+if (shouldReexecSourceDshForFetchProxy(
+  process.env,
+  sourceDshHttpProxyOverlayPresent(overlayUrl, fileText),
+)) {
+  process.env[SOURCE_DSH_PROXY_REEXEC_MARKER] = '1'
+  const child = spawn(process.execPath, [...process.execArgv, ...process.argv.slice(1)], {
+    env: { ...process.env },
+    stdio: 'inherit',
+  })
+  child.on('error', error => {
+    process.stderr.write(`dsh: ${error instanceof Error ? error.message : String(error)}\n`)
+    process.exit(1)
+  })
+  child.on('exit', (code, signal) => {
+    if (signal) {
+      process.kill(process.pid, signal)
+      return
+    }
+    process.exit(code ?? 1)
+  })
+} else {
+  await import('../apps/cli/src/bin.ts')
+}