fix(auth): include retry interval in pending device authorization error - #264

@masterkain Please check this just this once.

Thanks @jskorlol for the detailed diagnosis and proposed fix in PR #264

We independently reproduced the failure reported in issue #188: generic device-token 403/404 pending responses lacked retry_after_seconds, so the persisted flow treated a retryable response as a terminal token-exchange failure

What shipped on main:

• the generic 403/404 pending fallback now preserves the configured polling interval while discarding the raw provider body
• direct 403 and 404 regressions cover retry scheduling and redaction
• browser authorization URLs, device codes, and verification URLs have copy controls across link, relink, and the persistent cockpit card
• the shared clipboard control preserves feedback through LiveView polling patches

The retained findings landed independently in commit 6748fde7, rather than by merging or cherry-picking this branch. Attribution for the finding remains with you, and the landing commit preserves your co-authorship

Verification completed:

• focused Codex auth tests: 15 passed
• mix quality: passed
• the running LiveView was exercised through pending polling, copied-feedback persistence, fresh-flow replacement, cancellation, and mobile layout

The full suite was intentionally not rerun for the final test-only amendment

Closing PR #264 without merging because the confirmed work is now on main; nothing from its verified scope is deliberately left open