fix Garden shell integration

docs/plans/workflow-system.md

@@ -13,9 +13,10 @@ and add no abstraction without a demonstrated repeated need.
 - Branch: `chore/workflow-system`
 - Baseline: `nix flake check --no-build --quiet` passed on 2026-09-05; only
   the existing dirty-tree and unknown `modules` output warnings were emitted.
-- Next: activate the Nix-owned Garden tools on Zenith and run the credentialed
-  `just k8s test` workbench gate over the VPN. Then prove named database
-  connections and one Marimo-to-HTML report before expanding the workbench.
+- Next: activate the follow-up Garden shell fix, then remove the mutable Garden
+  binaries that still shadow the verified Nix-owned tools. Defer database and
+  Marimo artifacts until a concrete cross-system investigation supplies useful
+  content; proceed with an independent pilot in the meantime.
 
 ## Progress
 
@@ -23,7 +24,7 @@ and add no abstraction without a demonstrated repeated need.
 | --- | --- | --- |
 | Bootstrap and repository ownership | Waiting for user | Repository and dashboard reconciliation complete; credential cleanup remains |
 | Declarative workstation foundation | Complete | All-host builds pass with one Nixpkgs pin, `just`, and an explicit Podman Compose provider |
-| Repository contracts and workbench | Active | Three contracts and the local workbench are checkpointed; credentialed empirical gates remain |
+| Repository contracts and workbench | Active | Three contracts are checkpointed and the read-only test Kubernetes gate passed; API, database, and report evidence remain |
 | Desktop, agents, notes, PIM, transcription | Pending | Independent pilots follow foundation changes |
 | Conditional retirement and completion | Pending | Requires per-pilot evidence |
 
@@ -33,11 +34,12 @@ and add no abstraction without a demonstrated repeated need.
 | --- | --- | --- | --- |
 | NixOS configuration | `chore/workflow-system` | `41bc61b` | Discovery, paths, Git identity, and Codex defaults |
 | NixOS configuration | `chore/workflow-system` | `69552b7` | Simplify flake inputs and declare workstation lifecycle tools |
+| NixOS configuration | `chore/workflow-system` | `0c121a6` | Declare Garden tooling and the local workbench |
 | `yookr-dashboard-new` | `feat/gogv2` | `934605d` | Remove obsolete dashboard converter |
 | `rules-service` | `chore/workflow-contract` | `555d9cd` | Establish the first common repository contract |
 | `yookr-api` | `chore/workflow-contract` | `a76b2b7` | Establish the HTTP and OpenAPI contract |
 | `traceability-data-model` | `chore/workflow-contract` | `33cb7ff` | Establish the database and schema contract |
-| `yookr-workbench` | `main` | `6aae6d5` | Create the local-only cross-system workbench |
+| `yookr-workbench` | `main` | `733e7b7` | Create the workbench and isolate its Garden session |
 
 ## Human actions
 
@@ -55,11 +57,10 @@ and add no abstraction without a demonstrated repeated need.
   `just openapi-refresh test`; the current test deployment returns 404.
 - Populate the ignored API HTTP credentials and perform the planned login plus
   harmless administrator read; no credential-bearing request has been made.
-- Activate the Nix-owned Garden tools, verify `gardenctl` and `gardenlogin`,
-  then remove their duplicate binaries from `~/.garden` and `~/.local/bin`.
-- With the VPN active, run `just k8s test` in `yookr-workbench` and confirm the
-  test shoot opens read-only; this credentialed interactive gate has not been
-  run automatically.
+- Activate the follow-up Garden shell fix. The Nix-owned `gardenctl`,
+  `gardenlogin`, and `kubectl-gardenlogin` are verified under
+  `~/.nix-profile/bin`; afterward remove the duplicate mutable binaries
+  `~/.garden/gardenctl` and `~/.local/bin/{gardenctl,gardenlogin,kubectl-gardenlogin}`.
 - Destructive cleanup, credentials, activation, and empirical pilot decisions
   will be surfaced here before use.
 
@@ -117,10 +118,19 @@ and add no abstraction without a demonstrated repeated need.
   pinned `podman-compose` configuration validation pass.
 - Gardenctl 2.14.0 and Gardenlogin 0.10.0 are pinned from their official release
   assets; the hashes match the existing binaries byte-for-byte. All three host
-  builds pass, the OIDC kubectl plugin is declarative, and Zsh now consumes the
-  native `gardenctl rc zsh` output.
+  builds pass, the OIDC kubectl plugin is declarative, and Zsh consumes the
+  native `gardenctl rc zsh` output with its completion packaged declaratively.
 - The local-only `yookr-workbench` has no remote and initially owns only
   `just k8s test`. Each invocation creates an isolated Garden session, rejects
   every environment except test, and opens K9s read-only. Its flake check and
   command catalog pass, and the live rejection path exits before Garden access.
+- The user activated and rebooted into the Garden tooling, then confirmed that
+  `just k8s test` opens the test shoot in read-only K9s. The initial shell error
+  came from Garden writing completion into an absent Flatpak `$fpath` entry; the
+  initial target warning came from the fresh session inheriting its parent's
+  `KUBECONFIG`. Completion is now store-owned and the child recipe clears that
+  variable before targeting.
+- Named database connections and a Marimo-to-HTML report remain workbench
+  evaluation evidence, not scaffolding requirements. Add them only for a real
+  cross-system investigation that gives the queries and report durable value.
 - Run independent pilots in parallel, but gate every retirement separately.

modules/capabilities/dev-tools.nix

@@ -13,6 +13,8 @@
         dontUnpack = true;
         installPhase = ''
           install -Dm755 "$src" "$out/bin/gardenctl"
+          install -d "$out/share/zsh/site-functions"
+          "$out/bin/gardenctl" completion zsh > "$out/share/zsh/site-functions/_gardenctl"
         '';
       };
       gardenlogin = pkgs.stdenvNoCC.mkDerivation {

modules/capabilities/shell.nix

@@ -62,7 +62,7 @@
         '';
 
         initContent = ''
-          source <(gardenctl rc zsh)
+          source <(gardenctl rc zsh --no-completion)
 
           bindkey -v