feat(cli): colorized, columnized text output with line:col locations

Replace the per-line fmt.Println loop with writeTextFindings() in
cmd/glint/output.go. The new renderer:

- Aligns all findings into four space-separated columns: location,
  rule ID, severity, message — widths computed from the full finding
  set so all lines are flush
- Colors severity words when stdout is a TTY and NO_COLOR is not set:
  red+bold for "error", orange+bold for "warning"; location dimmed;
  rule ID bold
- Formats location as file:line:col when column is known, file:line
  otherwise, falling back to just file

To populate column numbers, add Column int to model.Job (set from
keyNode.Column in the YAML parser) and Finding.Column (set during
the checkJob source-location attachment pass and in the ten cross-job
check sites that explicitly set Line: job.Line).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cmd/glint/main.go

@@ -420,9 +420,7 @@ Examples:
 	case "github":
 		writeGitHub(os.Stdout, findings)
 	default: // "text"
-		for _, f := range findings {
-			fmt.Println(f)
-		}
+		writeTextFindings(os.Stdout, findings)
 	}
 
 	if len(findings) == 0 {

cmd/glint/output.go

@@ -0,0 +1,111 @@
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"git.k3nny.fr/glint/internal/linter"
+)
+
+// ANSI escape sequences used for colorized output.
+const (
+	ansiReset  = "\033[0m"
+	ansiBold   = "\033[1m"
+	ansiDim    = "\033[2m"
+	ansiRed    = "\033[31m"
+	ansiOrange = "\033[33m" // rendered as orange/amber in most terminals
+)
+
+// colorEnabled reports whether ANSI color should be used when writing to w.
+// Colors are suppressed when NO_COLOR is set or when w is not a terminal.
+func colorEnabled(w io.Writer) bool {
+	if os.Getenv("NO_COLOR") != "" {
+		return false
+	}
+	f, ok := w.(*os.File)
+	if !ok {
+		return false
+	}
+	fi, err := f.Stat()
+	return err == nil && (fi.Mode()&os.ModeCharDevice) != 0
+}
+
+// writeTextFindings prints findings in a columnized format with optional
+// ANSI color. All findings are scanned first to compute column widths so
+// that each field aligns across all output lines.
+//
+// Output columns (space-separated, no borders):
+//
+//	location   RULE   severity   message
+func writeTextFindings(w io.Writer, findings []linter.Finding) {
+	if len(findings) == 0 {
+		return
+	}
+
+	color := colorEnabled(w)
+
+	// Pre-compute locations and maximum location width.
+	locs := make([]string, len(findings))
+	maxLoc := 0
+	for i, f := range findings {
+		locs[i] = findingLocation(f)
+		if len(locs[i]) > maxLoc {
+			maxLoc = len(locs[i])
+		}
+	}
+
+	// Rule IDs are always 5 chars (GL001–GL999).
+	const ruleWidth = 5
+	// Severity width: "warning" = 7 chars.
+	const sevWidth = 7
+
+	for i, f := range findings {
+		loc := locs[i]
+		rule := f.Rule
+		sev := strings.ToLower(string(f.Severity))
+
+		msg := f.Message
+		if f.Job != "" {
+			msg = fmt.Sprintf("job %q: %s", f.Job, msg)
+		}
+
+		if color {
+			var sevSeq string
+			if f.Severity == linter.Error {
+				sevSeq = ansiRed + ansiBold
+			} else {
+				sevSeq = ansiOrange + ansiBold
+			}
+			fmt.Fprintf(w, "%s%-*s%s  %s%-*s%s  %s%-*s%s  %s\n",
+				ansiDim, maxLoc, loc, ansiReset,
+				ansiBold, ruleWidth, rule, ansiReset,
+				sevSeq, sevWidth, sev, ansiReset,
+				msg,
+			)
+		} else {
+			fmt.Fprintf(w, "%-*s  %-*s  %-*s  %s\n",
+				maxLoc, loc,
+				ruleWidth, rule,
+				sevWidth, sev,
+				msg,
+			)
+		}
+	}
+}
+
+// findingLocation formats the file:line:col location string for a finding.
+func findingLocation(f linter.Finding) string {
+	if f.File == "" {
+		return ""
+	}
+	switch {
+	case f.Line > 0 && f.Column > 0:
+		return fmt.Sprintf("%s:%d:%d", f.File, f.Line, f.Column)
+	case f.Line > 0:
+		return fmt.Sprintf("%s:%d", f.File, f.Line)
+	default:
+		return f.File
+	}
+}