feat: import agents_and_robots platform as unibots (Matrix-out, unibus transport)

Reemplaza el scaffold del echobot por la plataforma completa de bots traida
desde ~/DataProyects/Github/agents_and_robots tras la operacion Matrix-out:
los bots ya no hablan por Matrix sino por el bus unibus (modelo todo-rooms +
E2E via shell/transportunibus sobre github.com/enmanuel/unibus/pkg/client).

- go.mod: replace de unibus -> ../unibus y de fn-registry -> ../../../.. (paths
  relativos reajustados a la nueva ubicacion dentro de fn_registry).
- app.md: bump a 0.2.0, descripcion + arquitectura + comandos + gotchas reales.
- modulo Go conservado como github.com/enmanuel/agents (sin reescribir imports).

agents_and_robots queda archivado como museo de la era Matrix.

pkg/llm/router.go

@@ -0,0 +1,27 @@
+package llm
+
+import "strings"
+
+// Route maps a model string to its provider. Pure function.
+func Route(model string) ProviderID {
+	switch {
+	case model == "claude-code" || strings.HasPrefix(model, "claude-code/"):
+		return ProviderClaudeCode
+	case strings.HasPrefix(model, "claude"):
+		return ProviderAnthropic
+	case strings.HasPrefix(model, "gpt"), strings.HasPrefix(model, "o1"), strings.HasPrefix(model, "o3"):
+		return ProviderOpenAI
+	case strings.HasPrefix(model, "ollama/"):
+		return ProviderOllama
+	default:
+		return ProviderOpenAI
+	}
+}
+
+// ModelName strips the provider prefix from a model string.
+func ModelName(model string) string {
+	if after, ok := strings.CutPrefix(model, "ollama/"); ok {
+		return after
+	}
+	return model
+}

pkg/llm/router_test.go

@@ -0,0 +1,48 @@
+package llm
+
+import "testing"
+
+func TestRoute(t *testing.T) {
+	tests := []struct {
+		model string
+		want  ProviderID
+	}{
+		{"claude-code", ProviderClaudeCode},
+		{"claude-code/custom", ProviderClaudeCode},
+		{"claude-sonnet-4-5-20250929", ProviderAnthropic},
+		{"claude-opus-4", ProviderAnthropic},
+		{"gpt-4o", ProviderOpenAI},
+		{"o1-preview", ProviderOpenAI},
+		{"o3-mini", ProviderOpenAI},
+		{"ollama/mistral", ProviderOllama},
+		{"unknown-model", ProviderOpenAI}, // default
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.model, func(t *testing.T) {
+			got := Route(tt.model)
+			if got != tt.want {
+				t.Errorf("Route(%q) = %q, want %q", tt.model, got, tt.want)
+			}
+		})
+	}
+}
+
+func TestModelName(t *testing.T) {
+	tests := []struct {
+		input, want string
+	}{
+		{"ollama/mistral", "mistral"},
+		{"gpt-4o", "gpt-4o"},
+		{"claude-sonnet-4-5-20250929", "claude-sonnet-4-5-20250929"},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			got := ModelName(tt.input)
+			if got != tt.want {
+				t.Errorf("ModelName(%q) = %q, want %q", tt.input, got, tt.want)
+			}
+		})
+	}
+}

pkg/llm/types.go

@@ -0,0 +1,69 @@
+// Package llm defines pure types for LLM provider communication.
+// No side effects — only data and transformations.
+package llm
+
+import "context"
+
+type Role string
+
+const (
+	RoleSystem    Role = "system"
+	RoleUser      Role = "user"
+	RoleAssistant Role = "assistant"
+	RoleTool      Role = "tool"
+)
+
+type ProviderID string
+
+const (
+	ProviderAnthropic  ProviderID = "anthropic"
+	ProviderOpenAI     ProviderID = "openai"
+	ProviderOllama     ProviderID = "ollama"
+	ProviderClaudeCode ProviderID = "claude-code"
+)
+
+type Message struct {
+	Role       Role
+	Content    string
+	ToolCallID string
+	ToolCalls  []ToolCall
+}
+
+type ToolCall struct {
+	ID        string
+	Name      string
+	Arguments string // JSON-encoded
+}
+
+type ToolSpec struct {
+	Name        string
+	Description string
+	InputSchema map[string]any
+}
+
+type CompletionRequest struct {
+	Model       string
+	Messages    []Message
+	Tools       []ToolSpec
+	MaxTokens   int
+	Temperature float64
+	Stream      bool
+	SystemPrompt string
+}
+
+type TokenUsage struct {
+	InputTokens  int
+	OutputTokens int
+	TotalTokens  int
+}
+
+type CompletionResponse struct {
+	Content      string
+	ToolCalls    []ToolCall
+	Usage        TokenUsage
+	FinishReason string
+}
+
+// CompleteFunc is the single contract for LLM providers.
+// Implementations live in shell/llm/.
+type CompleteFunc func(ctx context.Context, req CompletionRequest) (CompletionResponse, error)