Current templates: safe.directory, golangci-lint v2.14.0, fetch-depth 0, the policy's last stage (closes #50)

REPO_POLICIES.md and .golangci.yml are the sneak/prompts next copies, and
.dockerignore takes the template's .git/modules/**/config line. The lint
phase runs golangci-lint v2.14.0; its two errors.AsType findings are
fixed. The stage that builds keyfunc marks /src safe for git, so a
context sent as a tar stream still yields a version. That stage is now
the last one and a development environment on the Debian Go image: what
script/bootstrap installs, the source in /src, keyfunc on the PATH. The
test phase uses the same image, so one Go image stays matched to
script/bootstrap. The CI checkout fetches all history and tags.

Model: opus-5-5

REPO_POLICIES.md

@@ -607,10 +607,10 @@ style conventions are in separate documents:
   settings.
 
 - Avoid putting files in the repo root unless necessary. Root should contain
-  only project-level config files (`README.md`, `Makefile`, `Dockerfile`,
-  `LICENSE`, `.gitignore`, `.editorconfig`, `REPO_POLICIES.md`, and
-  language-specific config). Everything else goes in a subdirectory. Canonical
-  subdirectory names:
+  only project-level config files (`README.md`, `AGENTS.md`, `Makefile`,
+  `Dockerfile`, `LICENSE`, `.gitignore`, `.editorconfig`, `REPO_POLICIES.md`,
+  and language-specific config). Everything else goes in a subdirectory.
+  Canonical subdirectory names:
     - `bin/` — executable scripts and tools
     - `cmd/` — Go command entrypoints; thin only: one `main.go` per binary whose
       body is a single call into `internal/` or `pkg/`, no project logic in
@@ -641,3 +641,7 @@ style conventions are in separate documents:
     - Go: `go.mod`, `go.sum`, `.golangci.yml`
     - JS: `package.json`, `yarn.lock`, `.prettierrc`, `.prettierignore`
     - Python: `pyproject.toml`
+
+- Guidance for coding agents lives in one `AGENTS.md` at the repository root. It
+  is never committed under a file or directory named after one agent tool, such
+  as `CLAUDE.md` or `.claude/`, and never split into separate memory files.