docs: examples for every hard requirement + mort migration blueprint

Phase 7: nine runnable examples/ programs (parse, failover chains with
trailing alias, tiers, LLM_* env providers, multimodal, tool loop,
Generate[T], agent, skills); docs/mort-migration.md mapping mort's
go-llm/go-agentkit usage onto majordomo APIs with the planned additive
library extensions and conversion order; README finalized with the
complete matrix.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

examples/multimodal/main.go

@@ -0,0 +1,47 @@
+// Command multimodal demonstrates capability-aware image input: attach an
+// image without knowing the target's limits — majordomo sniffs the real
+// format, downscales, re-encodes, and enforces counts/sizes against the
+// actual serving target before the request goes out.
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"os"
+
+	"gitea.stevedudenhoeffer.com/steve/majordomo"
+)
+
+func main() {
+	model := flag.String("model", "ollama-cloud/kimi-k2.6:cloud", "vision-capable model spec")
+	path := flag.String("image", "", "path to a jpeg/png/gif image (required)")
+	flag.Parse()
+
+	if *path == "" {
+		log.Fatal("usage: multimodal -image photo.jpg [-model spec]")
+	}
+	data, err := os.ReadFile(*path)
+	if err != nil {
+		log.Fatalf("read image: %v", err)
+	}
+
+	m, err := majordomo.Parse(*model)
+	if err != nil {
+		log.Fatalf("parse: %v", err)
+	}
+
+	// The declared MIME may even be wrong — the media pipeline sniffs the
+	// bytes and corrects it.
+	resp, err := m.Generate(context.Background(), majordomo.Request{
+		Messages: []majordomo.Message{majordomo.UserParts(
+			majordomo.Text("Describe this image in two sentences."),
+			majordomo.Image("image/jpeg", data),
+		)},
+	})
+	if err != nil {
+		log.Fatalf("generate: %v", err)
+	}
+	fmt.Printf("[%s] %s\n", resp.Model, resp.Text())
+}