Refactor cycle analytics stages (1st iteration)

See merge request !7647

Time tracking API

Closes #25861

See merge request !8483

Add a `:repository` trait to the `:empty_project` factory

See merge request !8605

New endpoints are:

POST :project_id/(issues|merge_requests)/(:issue_id|:merge_request_id)/time_estimate"

POST :project_id/(issues|merge_requests)/(:issue_id|:merge_request_id)/reset_time_estimate"

POST :project_id/(issues|merge_requests)/(:issue_id|:merge_request_id)/add_spent_time"

POST :project_id/(issues|merge_requests)/(:issue_id|:merge_request_id)/reset_spent_time"

GET  :project_id/(issues|merge_requests)/(:issue_id|:merge_request_id)/time_stats"

Resolve "Wrong file size on repository page"

Closes #26773

See merge request !8616

Correct documentation for `data_attribute` method

See merge request !8603

Backport timetracking to CE

See merge request !8195

Fixing typo

See merge request !8621

Fix Compare page throws 500 error when any branch/reference is not selected

Closes #25814

See merge request !8523

Copy commit SHA to clipboard

See merge request !8547

Right now this is a no-op. We're going to add it as a trait argument to
all existing usages of the `:project` factory, so that later we can flip
`:empty_project` to just be `:project`, forcing developers to opt-in to
the slower option when their tests truly require it.

Remove some useless require_relative statements

Closes #26756

See merge request !8609

Correctly keeps merge request tabs in place when editting value in

See merge request !8595

Disable all cops in .rubocop_todo.yml

See merge request !8610

Support `/merge` slash command for MRs

Closes #24915

See merge request !7746

Use cached values to compute total issues count in milestone index pages

See merge request !8518

Do not show artifacts keep button if not allowed

Closes #26357

See merge request !8501

Show 'too many changes' message for merge request

Closes #25017

See merge request !8444

Mark Commits as persisted

See merge request !8604

Cops with a max level are auto-generated with that set to the current
maximum, even when they're supposed to be ignored. For now, the best
option is to manually disable them.