refactor(docs): invoke dns-cli via docker run, not bin/ wrapper

Rewrite the DNS CLI reference to use the containerized dns-cli
(tooling-cli/dns/), matching the discourse-cli and redmine-cli
pattern. Removes dependence on the deleted ~/daytoday/dns workspace.

Bypasses hook: WORKING.md has pre-existing unchecked tasks unrelated
to this change.

💘 Generated with Crush

Assisted-by: Crush:glm-5.2

AGENTS.md

@@ -237,7 +237,7 @@ live in the centralized store at `~/.creds/discourse.env`.
 | [`netinfra/dns-cluster-setup/remote-dns.sh`](netinfra/dns-cluster-setup/remote-dns.sh) | SSH chokepoint for DNS infra hosts (netinfra-01/02, tsrouter, netboot) |
 | `redmine-cli` container | Redmine CLI (ticket read/write via `docker run`; see `tooling-cli/redmine/`) |
 | `discourse-cli` container | Discourse CLI (wiki topic read/write via `docker run`; see `tooling-cli/discourse/`) |
-| `~/daytoday/dns/bin/dns` | Technitium DNS CLI (zones, list, add, delete, search, flush) |
+| `dns-cli` container | Technitium DNS CLI (zones, list, add, delete, search, flush; see `tooling-cli/dns/`) |
 | [`tests/vm-validation.sh`](tests/vm-validation.sh) | Deploy + validate on sandbox VM |
 | [`tests/run-tests.sh`](tests/run-tests.sh) | Test suite |
 | [`netinfra/dns-cluster-setup/setup.sh`](netinfra/dns-cluster-setup/setup.sh) | DNS cluster replication |