feat(tui): add cards view, mode switching, promote picker, and card detail

Stream/cards toggle with 1/2 keys. Cards view with intent filtering
(tab cycles grab/read/fill/all), sort cycling (s key), pinned-first
ordering, and affordance badges. Promote picker (p key) with card type
selection and auto-detection from body content. Detail view renders
card_data per type: checklist steps, template slots, decision fields,
link URLs.

Extracts generateCardData to internal/carddata for reuse across cmd
and tui packages.

cmd/promote.go

@@ -1,11 +1,9 @@
 package cmd
 
 import (
-	"encoding/json"
 	"fmt"
-	"regexp"
-	"strings"
 
+	"github.com/lerko/nib/internal/carddata"
 	"github.com/lerko/nib/internal/db"
 	"github.com/lerko/nib/internal/display"
 	"github.com/spf13/cobra"
@@ -47,9 +45,9 @@ func runPromote(_ *cobra.Command, args []string) error {
 		return err
 	}
 
-	cardData := generateCardData(cardType, e.Body)
+	cd := carddata.GenerateCardData(cardType, e.Body)
 
-	if err := store.Promote(id, cardType, cardData); err != nil {
+	if err := store.Promote(id, cardType, cd); err != nil {
 		if err == db.ErrAlreadyPromoted {
 			return fmt.Errorf("invalid_promote — entity %s is already a %s",
 				display.FormatID(id), *e.CardType)
@@ -60,74 +58,3 @@ func runPromote(_ *cobra.Command, args []string) error {
 	fmt.Printf("promoted %s → %s\n", display.FormatID(id), cardType)
 	return nil
 }
-
-var templateSlotRe = regexp.MustCompile(`\$\{(\w+)\}`)
-
-func generateCardData(ct db.CardType, body string) *string {
-	var data string
-	switch ct {
-	case db.CardTemplate:
-		matches := templateSlotRe.FindAllStringSubmatch(body, -1)
-		type slot struct {
-			Name    string `json:"name"`
-			Default string `json:"default"`
-		}
-		var slots []slot
-		seen := map[string]bool{}
-		for _, m := range matches {
-			name := m[1]
-			if !seen[name] {
-				slots = append(slots, slot{Name: name, Default: ""})
-				seen[name] = true
-			}
-		}
-		if slots == nil {
-			slots = []slot{}
-		}
-		b, _ := json.Marshal(map[string]any{"slots": slots})
-		data = string(b)
-
-	case db.CardChecklist:
-		type step struct {
-			Text string `json:"text"`
-			Done bool   `json:"done"`
-		}
-		var steps []step
-		for _, line := range strings.Split(body, "\n") {
-			line = strings.TrimSpace(line)
-			if strings.HasPrefix(line, "[ ]") || strings.HasPrefix(line, "[x]") {
-				text := strings.TrimSpace(line[3:])
-				done := strings.HasPrefix(line, "[x]")
-				steps = append(steps, step{Text: text, Done: done})
-			}
-		}
-		if steps == nil {
-			steps = []step{{Text: body, Done: false}}
-		}
-		b, _ := json.Marshal(map[string]any{"steps": steps})
-		data = string(b)
-
-	case db.CardDecision:
-		b, _ := json.Marshal(map[string]any{
-			"chose":    "",
-			"why":      "",
-			"rejected": []string{},
-		})
-		data = string(b)
-
-	case db.CardLink:
-		url := ""
-		for _, word := range strings.Fields(body) {
-			if strings.HasPrefix(word, "http://") || strings.HasPrefix(word, "https://") {
-				url = word
-				break
-			}
-		}
-		b, _ := json.Marshal(map[string]any{"url": url})
-		data = string(b)
-
-	default:
-		data = "{}"
-	}
-	return &data
-}