feat(docs): /go/agent/ — first per-package landing replaces redirect

Demonstrates the migration pattern: drop a Starlight MDX page at
src/content/docs/go/<pkg>.mdx with a per-page head: override carrying the
package-specific go-import / go-source meta tags. The static redirect at
public/go/<pkg>/index.html gets removed so the Starlight page wins.

Result for /go/agent/:
  - Real docs page (sidebar entry under "Packages")
  - go-import meta = dappco.re/go/agent → github.com/dappcore/agent.git
    (page-level head replaces the global dappco.re/go default)
  - go-source likewise scoped to dappcore/agent

Same pattern applies for mcp, miner, pool, proxy, stream, tenant when
they're ready — each is a separate Starlight page + redirect removal.

Note Snider's path migration: post-rename consumers import
dappco.re/go/agent (not dappco.re/go/core/agent). The legacy core/
path keeps resolving via the unchanged public/go/core/agent/ redirect.

Co-Authored-By: Virgil <virgil@lethean.io>

Author: Snider

astro.config.mjs

@@ -50,6 +50,12 @@ export default defineConfig({
 						{ label: 'Errors', slug: 'go/error' },
 					],
 				},
+				{
+					label: 'Packages',
+					items: [
+						{ label: 'agent', slug: 'go/agent' },
+					],
+				},
 			],
 		}),
 	],

public/go/agent/index.html

@@ -0,0 +1,44 @@
+---
+title: agent
+description: Agent runtime for the dappcore ecosystem — dispatch, sessions, fleets, plans.
+head:
+  - tag: meta
+    attrs:
+      name: go-import
+      content: 'dappco.re/go/agent git https://github.com/dappcore/agent.git'
+  - tag: meta
+    attrs:
+      name: go-source
+      content: 'dappco.re/go/agent https://github.com/dappcore/agent https://github.com/dappcore/agent/tree/main{/dir} https://github.com/dappcore/agent/blob/main{/dir}/{file}#L{line}'
+---
+
+The agent package is the runtime layer for autonomous coding agents — dispatch
+pipeline, session state, fleet coordination, and plan execution. Built on the
+[`core/go`](/go/) primitives.
+
+## Install
+
+```sh
+go get dappco.re/go/agent@latest
+```
+
+## Import
+
+```go
+import "dappco.re/go/agent"
+```
+
+The path drops the legacy `core/` segment — `dappco.re/go/agent`, not
+`dappco.re/go/core/agent`. Existing consumers on the legacy path are still
+resolved by the redirect at [/go/core/agent/](/go/core/agent/) and continue
+to compile against the same source repo.
+
+## Status
+
+Page in flight — content fills in as the package converges. Source of truth
+today is the README and inline docstrings in the repo.
+
+## Source
+
+[`github.com/dappcore/agent`](https://github.com/dappcore/agent) — full source,
+issues, and releases.