PR 20275 — GitLab pasted repository lookup takeover

Original: 8 added cases across 3 definitions in one existing file.
Final: 7 added cases across 3 definitions; nine main tests preserved.
Pinned main with first reduced tests: 9 pass / 6 fail.
Original implementation with reduced tests: 14 pass / 1 fail (wrong web port).
First rebuild with followup tests: 14 pass / 2 fail (wrong install root and scheme-less HTTP config).
Before case comparison fix: 15 pass / 1 fail (existing HTTPS success row changed to mixed case).
Final: all 16 CLI tests and all 166 GitLab tests across six files pass.
Targeted lint/format, scoped GitLab typecheck, and git diff check pass.
Production SHA256: 5cbb6b44974b8fe7303278dac9dacc81f947363f84dc06790a145b38d6e2c774
Test SHA256: d70d5978a77def16b9bf078d0f387db7494bfafd961ee9eb457d7037d135832a

Integrated verification on headless Linux used the built-in T3 Browser and actual isolated development server with a fake glab subprocess. Public GitLab API JSON for gitlab-org/cli and synthetic self-hosted responses were fixtures. No authenticated glab or cloning.
Successful inputs: HTTPS URL, bare project path, SCP, SSH port 2222, scheme-less HTTP config with install root, HTTPS port 8443 with install root, and https://gitlab.com/GitLab-Org/CLI. All reach Create & Clone. Repeated-root fixture inputs request projects/gitlab%2Fteam%2Fapp (one root removed). Mixed-case input preserves projects/GitLab-Org%2FCLI argv and accepts canonical response gitlab-org/cli.
Rejected inputs: different hostname, different web port, same host and port with a different returned project path.
Live public GitLab API separately accepted GET /api/v4/projects/GitLab-Org%2FCLI and returned canonical path gitlab-org/cli.

Root-fix before/after images use the same synthetic fixture and 1280x800 viewport. Before is the first rebuild, not main. Configured https://example.com:8443/gitlab; pasted https://example.com:8443/other/team/app.git incorrectly offered /gitlab/other/team/app before the final response path validation. The same input is rejected after that fix. Final success images show the valid clone destination step.

Not verified: real authenticated glab, real self-hosted GitLab, actual cloning, macOS, Windows, iOS, Android, Electron desktop. The real-data snapshot could not migrate because installed-build migration history differs; isolated fresh worktree state was used. No live database changed. Human approval of host/install-root semantics remains a merge gate. No merge authorized.