chore: move wasmvm, python, browser, dev-shell, playground to agent-os repo

Packages moved to ~/a1 (agent-os) and renamed:
- @secure-exec/wasmvm -> @rivet-dev/agent-os-posix
- @secure-exec/python -> @rivet-dev/agent-os-python
- @secure-exec/browser -> @rivet-dev/agent-os-browser
- @secure-exec/dev-shell -> @rivet-dev/agent-os-dev-shell
- @secure-exec/playground -> @rivet-dev/agent-os-playground

Also moved: related tests, docs, and examples (doom, ai-agent-type-check).
Cleaned up browser re-exports, optional deps, and doc nav.

This repo now focuses on: kernel (@secure-exec/core), Node.js runtime
(@secure-exec/nodejs), V8 engine (@secure-exec/v8), TypeScript tools
(@secure-exec/typescript), and the barrel package (secure-exec).

Author: NathanFlurry

docs/api-reference.mdx

@@ -10,7 +10,6 @@ description: Complete reference for all secure-exec exports.
 | `secure-exec` | Main package — `createKernel`, `createNodeRuntime`, `NodeRuntime`, system drivers, filesystem, network, and permissions |
 | `@secure-exec/core` | Kernel, types, VFS, permission helpers, shared utilities |
 | `@secure-exec/nodejs` | Node.js runtime driver, bridge, execution driver, system driver factory |
-| `@secure-exec/python` | Python/Pyodide runtime driver |
 | `@secure-exec/typescript` | Sandboxed TypeScript compiler tools |
 
 ---

docs/architecture.mdx

@@ -178,9 +178,7 @@ flowchart TB
 - DNS operations return deterministic `ENOSYS` errors
 
 **Outside the worker (host):**
-- The browser isolate spawns workers, dispatches requests by ID, and correlates responses
-- `createBrowserDriver()` configures OPFS or in-memory filesystem and fetch-based networking
-- Node-only runtime options (like `memoryLimit`) are validated and rejected at creation time
+- `createNodeDriver()` configures filesystem, networking, and permissions
 
 ## Permission Flow
 

docs/docs.json

@@ -50,14 +50,12 @@
         "group": "System Drivers",
         "pages": [
           "system-drivers/overview",
-          "system-drivers/node",
-          "system-drivers/browser"
+          "system-drivers/node"
         ]
       },
       {
         "group": "Features",
         "pages": [
-          "features/typescript",
           "features/permissions",
           "features/filesystem",
           "features/virtual-filesystem",
@@ -97,14 +95,6 @@
       {
         "group": "Experimental",
         "pages": [
-          {
-            "group": "Runtimes",
-            "pages": [
-              "runtimes/overview",
-              "runtimes/node",
-              "runtimes/python"
-            ]
-          },
           {
             "group": "Kernel",
             "pages": [
@@ -115,20 +105,10 @@
               "kernel/interactive-shell"
             ]
           },
-          {
-            "group": "WasmVM",
-            "pages": [
-              "wasmvm/supported-commands"
-            ]
-          },
           {
             "group": "Reference",
             "pages": [
-              "posix-compatibility",
-              "os-test-conformance-report",
-              "libc-test-conformance-report",
-              "nodejs-conformance-report",
-              "python-compatibility"
+              "nodejs-conformance-report"
             ]
           }
         ]

docs/features/filesystem.mdx

@@ -57,22 +57,6 @@ try {
 
 Source: [examples/features/src/filesystem.ts](https://github.com/rivet-dev/secure-exec/blob/main/examples/features/src/filesystem.ts)
 
-## OPFS (browser)
-
-Persistent filesystem using the Origin Private File System API. This is the default for `createBrowserDriver()`.
-
-```ts
-import { createBrowserDriver } from "@secure-exec/browser";
-
-// OPFS (default)
-const driver = await createBrowserDriver({ filesystem: "opfs" });
-
-// In-memory fallback
-const memDriver = await createBrowserDriver({ filesystem: "memory" });
-```
-
-<Info>OPFS does not support atomic rename operations.</Info>
-
 ## Node filesystem
 
 Thin wrapper around Node.js `fs/promises`. Provides real host filesystem access (gated by permissions).

docs/features/networking.mdx

@@ -111,31 +111,16 @@ Source: [examples/features/src/networking.ts](https://github.com/rivet-dev/secur
 
 ## Quick setup
 
-<Tabs>
-  <Tab title="Node">
-    ```ts
-    import { createNodeDriver, allowAllNetwork } from "secure-exec";
-
-    const driver = createNodeDriver({
-      useDefaultNetwork: true,
-      permissions: { ...allowAllNetwork },
-    });
-    ```
-
-    The Node adapter supports `fetch`, DNS lookups, and low-level HTTP requests.
-  </Tab>
-  <Tab title="Browser">
-    ```ts
-    import { createBrowserDriver } from "@secure-exec/browser";
-
-    const driver = await createBrowserDriver({
-      useDefaultNetwork: true,
-    });
-    ```
-
-    The browser adapter supports `fetch` only. DNS and low-level HTTP are not available.
-  </Tab>
-</Tabs>
+```ts
+import { createNodeDriver, allowAllNetwork } from "secure-exec";
+
+const driver = createNodeDriver({
+  useDefaultNetwork: true,
+  permissions: { ...allowAllNetwork },
+});
+```
+
+The Node adapter supports `fetch`, DNS lookups, and low-level HTTP requests.
 
 ## Network adapters