feat: formatted JSON and certificates, errors in the status pane, no scope access list (#19)

**Formatted values.** A revealed value is shown as it reads best: JSON indented, and PEM certificates as subject, issuer, valid dates, names and SHA-1 thumbprint instead of base64. Any other PEM block (a private key in a bundle) is named, `EC PRIVATE KEY (not shown)`, never shown. Anything else shows as before. `y` copies the value exactly as stored, and the hints line says so (`JSON, formatted: y copies it as stored`).

**Errors in the status pane.** This session's errors, newest first, up to 20, with the time and what they were about (`12:32 kv-restricted: 403 Forbidden: …`): lists that couldn't load, values and details that couldn't be read, sources, saving the cache, and whatever the footer flashed (a failed copy) before you moved on. A repeat moves to the top. Sign-ins aren't listed (the footer and the account say those). Only the first line of each, and not kept after quitting. `y` copies one.

**No access list for Databricks scopes.** It was the one request of its own left (one call per scope). Removed with its tests and docs; refusals still say what to check.

**Copying over SSH: checked, nothing to change.** Over SSH (`SSH_TTY`/`SSH_CONNECTION`), `y` copies with OSC 52, and the 30-second clear works the same way. Your tmux (3.7, `set-clipboard on`) passes it through and kitty (`clipboard_control write-clipboard`) accepts it; docs/config.md already says what's needed.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Karl-Einar Bergstrøm <karl-einarb@outlook.com>
Reviewed-on: #19

internal/ui/panes/valueview_test.go

@@ -0,0 +1,60 @@
+package panes
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"math/big"
+	"slices"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestValueViewJSON(t *testing.T) {
+	lines, note := valueView(`{"user":"app","port":5432,"tags":["a"]}`)
+	want := []string{"{", `  "user": "app",`, `  "port": 5432,`, `  "tags": [`, `    "a"`, "  ]", "}"}
+	if !slices.Equal(lines, want) || note != "JSON, formatted" {
+		t.Errorf("lines %q, note %q", lines, note)
+	}
+	for _, v := range []string{"plain value", "{not json", "42", "line one\nline two"} {
+		if lines, note := valueView(v); note != "" || strings.Join(lines, "\n") != v {
+			t.Errorf("%q shown as %q (%q)", v, lines, note)
+		}
+	}
+}
+
+func TestValueViewCertificate(t *testing.T) {
+	key, _ := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	tmpl := &x509.Certificate{
+		SerialNumber: big.NewInt(1), Subject: pkix.Name{CommonName: "app.example.com"},
+		DNSNames:  []string{"app.example.com", "www.app.example.com"},
+		NotBefore: time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC), NotAfter: time.Date(2027, 1, 1, 0, 0, 0, 0, time.UTC),
+	}
+	der, err := x509.CreateCertificate(rand.Reader, tmpl, tmpl, &key.PublicKey, key)
+	if err != nil {
+		t.Fatal(err)
+	}
+	keyDER, _ := x509.MarshalECPrivateKey(key)
+	bundle := string(pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: der})) +
+		string(pem.EncodeToMemory(&pem.Block{Type: "EC PRIVATE KEY", Bytes: keyDER}))
+
+	lines, note := valueView(bundle)
+	text := strings.Join(lines, "\n")
+	for _, want := range []string{"subject  CN=app.example.com", "valid    2026-01-01 to 2027-01-01",
+		"names    app.example.com, www.app.example.com", "SHA-1    ", "EC PRIVATE KEY (not shown)"} {
+		if !strings.Contains(text, want) {
+			t.Errorf("missing %q:\n%s", want, text)
+		}
+	}
+	if note != "certificate" || strings.Contains(text, "BEGIN") {
+		t.Errorf("note %q, or PEM shown:\n%s", note, text)
+	}
+	// A private key alone isn't a certificate: shown as it is.
+	if _, note := valueView(string(pem.EncodeToMemory(&pem.Block{Type: "EC PRIVATE KEY", Bytes: keyDER}))); note != "" {
+		t.Errorf("a key alone: note %q", note)
+	}
+}