refactor(gitea/mod): selective re-exports replace 6 star re-exports (ADR-025 L3)

gitea/mod.nu had 6 `export use X *`. Each is now explicit.

Symbol counts per target:
  api_client.nu        28
  service.nu           10
  workspace_git.nu     17
  locking.nu            9
  extension_publish.nu  6
  commands.nu          24  (all multi-word "gitea X")

Total: 94 symbols, 24 quoted multi-word Nu subcommands.

Validation:
  nu --ide-check 50 gitea/mod.nu -> 50 errors (all PRE-EXISTING)
    Verified by stash-and-compare: the unmodified original mod.nu also
    produced 50 errors from the same imported files. Zero errors
    introduced by this refactor.

Refs: ADR-025, .coder/benchmarks/phase2-transitivity.md Layer 3

nulib/lib_provisioning/gitea/mod.nu

@@ -4,10 +4,45 @@
 #
 # Version: 1.0.0
 
-# Export all submodules
+# gitea/ subsystem facade — selective re-exports (ADR-025 Phase 3 Layer 3).
-export use api_client.nu *
+
-export use service.nu *
+export use api_client.nu [
-export use workspace_git.nu *
+    close-issue create-branch create-issue create-organization create-release
-export use locking.nu *
+    create-repository create-tag delete-release delete-repository get-api-url
-export use extension_publish.nu *
+    get-branch get-current-user get-gitea-config get-gitea-token get-issue
-export use commands.nu *
+    get-organization get-release-by-tag get-repository gitea-api-call
+    list-branches list-issues list-organizations list-releases list-repositories
+    list-tags list-user-repositories upload-release-asset validate-token
+]
+export use service.nu [
+    check-gitea-health get-gitea-logs get-gitea-status install-gitea
+    restart-gitea start-gitea start-gitea-binary start-gitea-docker
+    stop-gitea stop-gitea-docker
+]
+export use workspace_git.nu [
+    clone-workspace create-workspace-branch create-workspace-repo
+    delete-workspace-branch get-workspace-diff get-workspace-git-status
+    get-workspace-remote-info has-uncommitted-changes init-workspace-git
+    list-workspace-branches list-workspace-stashes pop-workspace-stash
+    pull-workspace push-workspace stash-workspace-changes
+    switch-workspace-branch sync-workspace
+]
+export use locking.nu [
+    acquire-workspace-lock cleanup-expired-locks force-release-lock
+    get-lock-info is-workspace-locked list-all-locks list-workspace-locks
+    release-workspace-lock with-workspace-lock
+]
+export use extension_publish.nu [
+    download-gitea-extension get-gitea-extension-metadata
+    get-latest-extension-version list-gitea-extensions
+    publish-extension-to-gitea publish-extensions-batch
+]
+export use commands.nu [
+    "gitea auth validate" "gitea extension download" "gitea extension info"
+    "gitea extension list" "gitea extension publish" "gitea help"
+    "gitea install" "gitea lock acquire" "gitea lock cleanup"
+    "gitea lock force-release" "gitea lock info" "gitea lock list"
+    "gitea lock release" "gitea logs" "gitea org create" "gitea org list"
+    "gitea repo create" "gitea repo delete" "gitea repo list"
+    "gitea restart" "gitea start" "gitea status" "gitea stop" "gitea user"
+]