docs: update merged blog post links to /add-ons; drop leftover helpers nav

Author: antfubot

docs/content/4.helpers/.navigation.yml

@@ -140,13 +140,13 @@ We are still exploring the APIs and practices around discoverability, permission
 
 ### Built-in Devframes
 
-Real tools make the abstraction convincing. To test Devframe's capabilities and framework-neutral design, we ship a few [built-in devframes](/plugins) as reusable working examples. They intentionally use **different UI frameworks**, and each can run through a standalone adapter or mount into a supported host framework.
+Real tools make the abstraction convincing. To test Devframe's capabilities and framework-neutral design, we ship a few [built-in devframes](/add-ons) as reusable working examples. They intentionally use **different UI frameworks**, and each can run through a standalone adapter or mount into a supported host framework.
 
 Here are a few examples:
 
 #### Data Inspector
 
-[`@devframes/plugin-data-inspector`](/plugins/data-inspector) is built with Vue and provides an interactive workbench for live node-side objects. A tool can register an object as a data source, then explore and query it with [Jora](https://discoveryjs.github.io/jora/) inside the process that owns it.
+[`@devframes/plugin-data-inspector`](/add-ons/devframes/data-inspector) is built with Vue and provides an interactive workbench for live node-side objects. A tool can register an object as a data source, then explore and query it with [Jora](https://discoveryjs.github.io/jora/) inside the process that owns it.
 
 Through its standalone adapters, it can inspect JSON or JSONL files, build a self-contained report, or attach to a running Node.js process. This is useful for inspecting stores, caches, framework contexts, build metadata, or other states that usually require custom logging.
 
@@ -165,7 +165,7 @@ When mounted, other tools contribute data sources. A Vite plugin could expose it
 
 #### Terminals
 
-[`@devframes/plugin-terminals`](/plugins/terminals) is built with Svelte and provides a browser-based terminal panel supporting read-only process output and interactive PTY sessions.
+[`@devframes/plugin-terminals`](/add-ons/devframes/terminals) is built with Svelte and provides a browser-based terminal panel supporting read-only process output and interactive PTY sessions.
 
 This separates the process-running capability from the tool that renders it. A DevTools host can give multiple tools a consistent place for subprocess output and interactive commands while keeping the user's main terminal focused.
 
@@ -189,7 +189,7 @@ This opens the interactive terminal directly in your browser. You can use it to
 
 #### Accessibility Inspector
 
-[`@devframes/plugin-a11y`](/plugins/a11y) is built with Solid. Its page script scans the user app with [axe-core](https://github.com/dequelabs/axe-core), lists WCAG violations, and highlights the corresponding elements on the page. It can also turn the findings into fix prompts for coding agents, connecting visual inspection with a coding-agent workflow.
+[`@devframes/plugin-a11y`](/add-ons/devframes/a11y) is built with Solid. Its page script scans the user app with [axe-core](https://github.com/dequelabs/axe-core), lists WCAG violations, and highlights the corresponding elements on the page. It can also turn the findings into fix prompts for coding agents, connecting visual inspection with a coding-agent workflow.
 
 With a standalone adapter, its panel and page script can inspect any page. Inside a DevTools host, the same findings can also be mirrored into the shared message feed.
 
@@ -202,7 +202,7 @@ It is heavily inspired by [`@nuxt/a11y`](https://github.com/nuxt/a11y), which br
 
 #### More Built-in Devframes
 
-Other built-in devframes cover a [VS Code editor on the web](/plugins/code-server), [asset management](/plugins/assets), a [Git panel](/plugins/git), [Open Graph previews](/plugins/og), and [Devframe's own RPC and state inspector](/plugins/inspect). They share the devframe definition and protocol while each chooses its own UI framework.
+Other built-in devframes cover a [VS Code editor on the web](/add-ons/devframes/code-server), [asset management](/add-ons/devframes/assets), a [Git panel](/add-ons/devframes/git), [Open Graph previews](/add-ons/devframes/og), and [Devframe's own RPC and state inspector](/add-ons/devframes/inspect). They share the devframe definition and protocol while each chooses its own UI framework.
 
 These built-in devframes show what Devframe can support and offer starting points for communities to build their own. We believe many more interesting DevTools will emerge over time. You can follow the growing list on [Built with Devframe](/guide/built-with).