feat: port CLI, TUI, and launcher from v1.5 into v2 (#1452)

Ports the CLI, TUI, and launcher from v1.5 into v2 behind a single
`mcp-inspector` entrypoint (launcher → web/cli/tui). Includes the
`mcp-inspector --web --dev` launcher fix (Vite alias resolution + prod-server
double-start), the root `postinstall` install cascade with simplified CI, and
spec/AGENTS docs (no-workspaces rationale, Development setup).

Closes #1246.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/tui/src/logger.ts

@@ -0,0 +1,30 @@
+import path from "node:path";
+import pino from "pino";
+import type { Logger } from "pino";
+
+let tuiLoggerInstance: Logger | undefined;
+
+/**
+ * TUI file logger for auth and InspectorClient events.
+ * Writes to ~/.mcp-inspector/auth.log so TUI console output is not corrupted.
+ * Lazy-initialized so --help and other early exits never open the log stream.
+ */
+export function getTuiLogger(): Logger {
+  if (!tuiLoggerInstance) {
+    const logDir =
+      process.env.MCP_INSPECTOR_LOG_DIR ??
+      path.join(
+        process.env.HOME || process.env.USERPROFILE || ".",
+        ".mcp-inspector",
+      );
+    const logPath = path.join(logDir, "auth.log");
+    tuiLoggerInstance = pino(
+      {
+        name: "mcp-inspector-tui",
+        level: process.env.LOG_LEVEL ?? "info",
+      },
+      pino.destination({ dest: logPath, append: true, mkdir: true }),
+    );
+  }
+  return tuiLoggerInstance;
+}