Consolidate two project secret columns into one

[momesgin]

Summary

Fixes #14892

Occurred changes and/or fixed issues

• Consolidated the "Created by Project Secret" and "Project Secret" columns in the Secrets list into a single "Origin" column.
• Added a new SecretOrigin formatter component to handle the display logic for the new column.
• The "Origin" column displays:
  • "Project Secret" for Project Scoped Secrets (with a tooltip showing the project and cluster).
  • "Via Project Secret" for secrets created by a Project Scoped Secret (with a tooltip showing the source secret and project).
• Added optional chaining to the project lookup in shell/edit/secret/index.vue to prevent potential runtime errors.

Technical notes summary

• Replaced SECRET_CLONE and SECRET_PROJECT_SCOPED headers with SECRET_ORIGIN in shell/config/table-headers.js and shell/list/secret.vue.
• The new SecretOrigin.vue component handles fetching necessary project/cluster data for the tooltip if it's missing from the store.
• Removed the now unused clusterAndProjectLabel getter from shell/models/secret.js.
• Sorting for the new column is based on the management.cattle.io/project-scoped-secret-copy annotation.

Areas or cases that should be tested

Make sure to enable this option "Show dynamic Namespaces managed by Rancher (not intended for editing or deletion)" in preferences to be able to see the PSS created from downstream clusters in the local's secrets list page.

• Secrets List:
  • Verify that standard secrets have an empty or dash indicator in the "Origin" column.
  • Verify that Project Scoped Secrets display "Project Secret" in the "Origin" column.
  • Verify that Copied Secrets (created by a Project Scoped Secret) display "Via Project Secret".
  • Hover over the values in the "Origin" column to ensure the tooltips display the correct project/cluster information.

Areas which could experience regressions

• Secrets list table layout and sorting behaviour.
• Test sorting by the "Origin" column to ensure it behaves as before.
• Tooltip display for secrets with missing project/cluster metadata.

Screenshot/Video

Checklist

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[momesgin]

this was not needed anymore

[richard-cox]

Just two small comments, with suggested updates, otherwise looks good.

Appreciated the inline comments as well