Fix Turkish locale in the plugin manifest schema

[Egv2]

Problem and result

Follow-up to #462. The schema's required locale lists gained tr, but the matching properties entries in completeLocalizedText and completeLocalizedStringArrays were missed, so with additionalProperties: false Turkish is both required and forbidden and every plugin manifest fails JSON Schema validation on main. This adds the missing tr properties so the manifests validate again.

Changes

Two properties maps in docs/plugins/plugin-manifest.schema.json now include tr.

Verification

• jsonschema validation of all 63 plugin manifests: 63 of 63 failed on main, 62 of 63 pass with this fix. The one remaining failure is pre-existing and unrelated, the permission enum lacks full-disk-access that DiskClean declares and the Python validator accepts. Happy to fix that separately if wanted.
• make script-tests: 221 tests pass.

UI evidence

Not applicable, schema documentation only.

Checklist

• Core behavior and relevant risks are verified using existing tests, focused additions, or manual checks; results or limitations are recorded.
• UI evidence is attached where applicable; shared components, themes, localization, and accessibility are respected.
• User-facing documentation and changelog fragments are updated when required.
• Plugin metadata, runtime contracts, action policies, and minimum-host compatibility agree.
• Licensing and third-party notices are complete; no credentials, local configuration, or unrelated generated files are included.