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/tools/registry.go

@@ -0,0 +1,58 @@
+// Package tools defines pure, declarative tool specifications.
+// No execution happens here — only data describing what tools exist and their contracts.
+package tools
+
+// ToolKind identifies the category of a tool.
+type ToolKind string
+
+const (
+	ToolKindSSH     ToolKind = "ssh"
+	ToolKindHTTP    ToolKind = "http"
+	ToolKindScript  ToolKind = "script"
+	ToolKindFileOps ToolKind = "file_ops"
+	ToolKindMCP     ToolKind = "mcp"
+)
+
+// ToolSpec is a pure description of a tool — what it does and what it accepts.
+// The actual execution lives in shell/effects/.
+type ToolSpec struct {
+	Name        string
+	Kind        ToolKind
+	Description string
+	Parameters  []ParameterSpec
+}
+
+type ParameterSpec struct {
+	Name        string
+	Type        string
+	Description string
+	Required    bool
+}
+
+// Registry is a map of available tools, keyed by name.
+type Registry map[string]ToolSpec
+
+// Add returns a new Registry with the given spec added.
+func (r Registry) Add(spec ToolSpec) Registry {
+	out := make(Registry, len(r)+1)
+	for k, v := range r {
+		out[k] = v
+	}
+	out[spec.Name] = spec
+	return out
+}
+
+// Get looks up a tool spec by name.
+func (r Registry) Get(name string) (ToolSpec, bool) {
+	spec, ok := r[name]
+	return spec, ok
+}
+
+// Names returns all registered tool names.
+func (r Registry) Names() []string {
+	names := make([]string, 0, len(r))
+	for k := range r {
+		names = append(names, k)
+	}
+	return names
+}

pkg/tools/specs.go

@@ -0,0 +1,37 @@
+package tools
+
+// SSHCommandSpec describes an SSH command to execute. Pure data — no execution.
+type SSHCommandSpec struct {
+	Target  string // references a named target in ssh config
+	Command string
+	Timeout string
+}
+
+// HTTPCallSpec describes an HTTP call to make. Pure data.
+type HTTPCallSpec struct {
+	Method  string
+	URL     string
+	Headers map[string]string
+	Body    string
+	Timeout string
+}
+
+// ScriptSpec describes a script to run. Pure data.
+type ScriptSpec struct {
+	Name    string
+	Args    []string
+	Timeout string
+}
+
+// FileOpsSpec describes a file operation. Pure data.
+type FileOpsSpec struct {
+	Op   string // read | write | list | delete
+	Path string
+}
+
+// MCPCallSpec describes a call to an MCP server. Pure data.
+type MCPCallSpec struct {
+	ServerName string
+	ToolName   string
+	Arguments  map[string]any
+}