docs: link the guides instead of importing them

AGENTS.md

@@ -2,10 +2,10 @@
 
 Test: `just test` | Before committing: `just ready`
 
-Read @CONTRIBUTING.md first. It covers prerequisites, setup, project structure,
-code standards, testing, input validation, and how to add an API domain. All of
-which apply to agents exactly as they apply to people. This file carries only
-what is specific to agents.
+Read [CONTRIBUTING.md](CONTRIBUTING.md) first. It covers prerequisites, setup,
+project structure, code standards, testing, input validation, and how to add an
+API domain. All of which apply to agents exactly as they apply to people. This
+file carries only what is specific to agents.
 
 ## Running tools
 
@@ -28,13 +28,13 @@ treating the failure as real.
 `go build ./...` and `go test ./...` fail in this repository. The UI is embedded
 via `//go:embed dist/*`, which requires `ui/dist/` to hold files at compile
 time. Use `just build`, `just test`, or `just ready`. Each builds the UI first.
-See @CONTRIBUTING.md under "Building and running".
+See [CONTRIBUTING.md](CONTRIBUTING.md#building-and-running).
 
 ## Where the rules come from
 
-@CONTRIBUTING.md names the specification under "Before you start". When a
-convention here and the specification disagree, the specification wins. Say so
-rather than following the code.
+[CONTRIBUTING.md](CONTRIBUTING.md#before-you-start) names the specification.
+When a convention here and the specification disagree, the specification wins.
+Say so rather than following the code.
 
 ## Commit trailer
 

CLAUDE.md

@@ -1,7 +1,7 @@
 # Claude Code
 
-All agent guidance lives in @AGENTS.md: how to invoke tools, why the Go
-toolchain is never called directly, where the rules come from, the commit
+All agent guidance lives in [AGENTS.md](AGENTS.md): how to invoke tools, why the
+Go toolchain is never called directly, where the rules come from, the commit
 trailer, and task tracking. This file exists so Claude Code finds it; the
 content is upstream.