test(external): add unit tests for create-from-template action

[dj4oC]

Description

Adds unit test coverage for the "create from template" action extension
(useActionExtensionCreateFromTemplate in
packages/web-app-external/src/extensions/createFromTemplate.ts), which was
introduced in #11775 and previously had no tests (no tests/unit/extensions/
directory existed).

New file: packages/web-app-external/tests/unit/extensions/createFromTemplate.spec.ts.

isVisible cases covered:

• more than one resource selected → false
• no personal space present → false
• resource not downloadable → false
• no matching app-provider template mime type → false
• single matching template resource → true

handler cases covered:

• successful file creation and navigation to the editor route with the correct
  contextRouteName/contextRouteParams/contextRouteQuery params
• duplicate-filename resolution via resolveFileNameDuplicate when a file of the
  same name already exists in the personal space root
• error path where showErrorMessage is called when the webdav listFiles call
  or createFileHandler throws

Related Issue

• Fixes Unit test coverage for "create from template" feature #11786

Motivation and Context

The action was shipped without unit tests. These tests pin down the visibility
predicate and the create/navigate/error flow so future changes to the extension
are guarded.

How Has This Been Tested?

• test environment: pnpm --filter external test:unit (vitest 4.1.6, node 22)
• result: Test Files 1 passed, Tests 9 passed (9)
• coverage on src/extensions/createFromTemplate.ts: 97.56% lines, 100%
  branches, 88.88% funcs (well above the 85% target; the single uncovered
  function is the label() getter, which is not part of the acceptance criteria)
• eslint on the new file: clean
• prettier --check: clean
• full-repo vue-tsc --noEmit: no type errors

This is a test-only change — no product code is modified.

Documentation checklist

• Changelog: added changelog/unreleased/change-add-create-from-template-tests.
• REUSE/SPDX headers: not applicable — this repo uses a single root LICENSE
  and carries no per-file SPDX headers on any existing source or test file, so
  none were added, to stay consistent with the codebase.
• Admin/end-user docs, WCAG note, OTEL metrics: not applicable (no behaviour or
  UI change).

Phase 4 pre-flight review (non-blocking findings): none — the change adds an
isolated spec with fully mocked dependencies (no network, deterministic).

Risk level: minimal (adds tests only).

Open tasks:

• none

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🤖 Automated by Claude Code

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[kw-security]

✅ Snyk checks have passed. No issues have been found so far.

Status	Scan Engine	Critical	High	Medium	Low	Total (0)
✅	Open Source Security	0	0	0	0	0 issues
✅	Licenses	0	0	0	0	0 issues
✅	Code Security	0	0	0	0	0 issues

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[dj4oC]

Superseded by owncloud/ocis#12544.

The owncloud/web frontend has been consolidated into owncloud/ocis (under web/), so this test coverage has been moved there. Closing in favour of the ocis PR.

🤖 Automated by Claude Code

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Generated by Claude Code