guide: read-only guided manual-rotation layer (links + worklist + TUI)

Advances the guided-rotation goal without rotating anything.

- internal/links: offline change-password URL generation — curated per-service
  table + RFC 8615 /.well-known/change-password + parent-domain fallback; derives
  a web host from a credential (git/netrc "user @ host", docker registry, aws)
- internal/worklist: secrets-free rotation worklist (source, identity, auto/manual,
  link) + Markdown renderer
- internal/tui: Bubble Tea walk-through (one credential per screen, open link,
  mark done/skip, progress) — READ-ONLY, enters/stores no secret
- cmd: `incredigo worklist` (offline, stdout/--out) and `incredigo guide` (TUI)
- tests: link derivation, worklist build/markdown + no-secret-column, TUI
  navigation/done/quit/view

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

internal/worklist/worklist.go

@@ -0,0 +1,65 @@
+// Package worklist turns discovered credentials into a rotation worklist: per
+// credential, whether it can be auto-rotated (a driver exists) or is manual, and
+// the page to rotate it on. It contains NO secrets — only non-secret metadata and
+// links — so a worklist is safe to write to disk or print.
+package worklist
+
+import (
+	"fmt"
+	"strings"
+
+	"incredigo/internal/discover"
+	"incredigo/internal/links"
+	"incredigo/internal/rotate"
+)
+
+// Item is one credential's rotation entry.
+type Item struct {
+	Index      int
+	Credential discover.Credential
+	Driver     string // "" when no rotation driver handles it (manual)
+	Link       links.Link
+}
+
+// Manual reports whether this credential has no automated rotation path today.
+func (it Item) Manual() bool { return it.Driver == "" }
+
+// Build classifies credentials (via the rotate registry) and attaches links.
+// With no drivers registered every Item is Manual.
+func Build(creds []discover.Credential) []Item {
+	plans := rotate.PlanAll(creds)
+	items := make([]Item, len(plans))
+	for i, p := range plans {
+		items[i] = Item{
+			Index:      i + 1,
+			Credential: p.Credential,
+			Driver:     p.Driver,
+			Link:       links.LinkFor(p.Credential),
+		}
+	}
+	return items
+}
+
+// Markdown renders a worklist as a Markdown document (no secrets).
+func Markdown(items []Item) string {
+	var b strings.Builder
+	b.WriteString("# incredigo rotation worklist\n\n")
+	fmt.Fprintf(&b, "%d credential(s). No secrets are included in this file.\n\n", len(items))
+	b.WriteString("| # | source | identity | rotation | change-password link |\n")
+	b.WriteString("|---|--------|----------|----------|----------------------|\n")
+	for _, it := range items {
+		rot := "manual"
+		if !it.Manual() {
+			rot = "auto: " + it.Driver
+		}
+		url := it.Link.URL
+		if url == "" {
+			url = "— (no web page)"
+		}
+		fmt.Fprintf(&b, "| %d | %s | %s | %s | %s |\n",
+			it.Index, it.Credential.Source, it.Credential.Identity, rot, url)
+	}
+	b.WriteString("\nGenerated by incredigo. Links are derived offline ")
+	b.WriteString("(curated table or RFC 8615 /.well-known/change-password).\n")
+	return b.String()
+}