feat(filter): support @me and currentUser macros in task assignee queries

[mcassaniti]

Resolves #3413

What this PR does

1. Backend Dynamic Macro Resolution (pkg/models/task_search.go):

   • Added resolveCurrentUserMacros in dbTaskSearcher.Search.
   • Filter query terms matching @me, currentUser, or current_user in assignee queries dynamically resolve to the logged-in user's username (web.Auth). UPDATE: Now only @me.
   • The stored filter expression in the database retains @me so shared views resolve dynamically per user.

2. Backend Unit Tests (pkg/models/task_search_test.go):

   • Added TestTaskSearchCurrentUserMacro testing string, slice, and array macro replacement.

3. Frontend UX & Docs (FilterAutocomplete.ts & FilterInputDocs.vue):

   • Prepended @me (Current User (@me)) to autocomplete suggestions for assignees.
   • Added assignees in @me example to the filter help documentation.

Testing

• Go unit test TestTaskSearchCurrentUserMacro passed.
• 1,084 frontend Vitest unit tests passed.

Disclaimer: This PR was prepared with AI assistant pair programming. All code changes, database queries, unit tests, and commits have been reviewed, GPG-signed, and verified against the repository build pipeline.

[kolaente]

What happens when a user has me as their username?

[mcassaniti]

Good question. For the frontend, the auto-complete will not match. Something like @m will however. This is why the frontend code uses startsWith(). The backend has exact matching regardless --> 'me' != '@me'.

I guess the code should reserve these special values and not allow them as a username. I'm fine if you want to change what is matched (e.g.: only currentUser is a valid pattern).

[ultinate]

Proposal: Only use @me as pattern. Not currentUser or current_user to avoid any conflicts with actual user names. This could extend to future patterns like @all or @admins.

This assumes that usernames starting with @ are not allowed.

[mcassaniti]

Done. The filter is restricted to @me only.