D64 — Connect UX: per-field hints, retry with populated form, persistent default, pre-connect probe (WP8)

Context. Four frictions in the connect flow: the "Token env" field mistaken for the token itself; on error the typed values were lost (CLI exited with exit 2); doDisconnect deleted .cartographer.yaml, so the next connect restarted from localhost even on machines pointed at a real server; no validation at submit (errors discovered only at a "deferred" sync).

Decision. 1. Per-field hints (fieldHint): "Token env var" label with a contextual hint clarifying it is the env var's name, not the token; ignored if Auth is off. 2. Error → form re-presented with the entered values: errMsg/forceRetry in connectFormModel, inline error, connect stays idempotent (no disconnect needed to retry). 3. Persistent default server: doDisconnect clears only agents in .cartographer.yaml, preserving server_url/trust/kbs as prefill; new env CARTOGRAPHER_SERVER_URL. 4. Pre-connect probe with force-override: new client.Ping(timeout) (JSON-RPC ping, 5s) at submit, before writing files; on failure the form returns with the error, but a second consecutive submit with no changes skips the probe and proceeds (server temporarily down with a valid config) — CLI equivalent via y/N prompt. Discarded alternatives. Skipping the Token env field from the tab order with Auth off (complicates the focus cycle for little gain); tools/list/initialize as probe (ping is cheaper); blocking probe without override (it would prevent saving a correct config with the server down). Details: docs/configurator.md §cartographer connect [provider|all]. Follow-up (July 2026). Point 3 preserved server_url in .cartographer.yaml, but only the interactive form re-read it as prefill: in the non-interactive path (--no-input, non-TTY) cmdConnect built opts from the flags' defaults, so a bare connect <agent> on a machine already pointed at a remote server rewrote the shared config to http://localhost:8080 / auth:false. Now the flag > config > default precedence also applies there: resolveConnectSettings (a pure, tested function) inherits server_url/auth/token_env from the existing .cartographer.yaml for each flag not passed explicitly.