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

Brings keyfunc to the current sneak/prompts templates: REPO_POLICIES.md and .golangci.yml are the template copies, the lint phase runs golangci-lint v2.14.0 on the template digest (its one new finding fixed), and .dockerignore gains the template line for submodule configs. The stage that compiles keyfunc marks /src safe for git, so a context sent as a tar stream still stamps the tag or short commit. The last stage is now a development environment, as the policy asks of a non-server repo: run the tool as docker run IMAGE keyfunc .... The CI checkout fetches tags.

Deviation: .gitea/workflows/check.yml differs from the template copy by fetch-depth: 0, which REPO_POLICIES.md requires.

Model: opus-5-5

.dockerignore

@@ -17,7 +17,10 @@
 # stage that compiles runs `git describe --tags --always` on .git, which
 # does not need .git/config; that file can hold a credential, such as a
 # password in a remote URL or the token the CI checkout step stores there.
+# Each submodule keeps a config with the same exposure in its git directory
+# under .git/modules/, nested again for a submodule's own submodules.
 .git/config
+.git/modules/**/config
 
 # Agent scratch: one full checkout of the repo per in-flight agent.
 # Anchored because it occurs once where agents run at the repo root.