Add missing validations for required fields to module schema v1

[pditommaso]

Summary

Introduces module/v1.1/schema.json alongside the existing v1. The new revision tightens validation so that meta.yml files cannot be published with placeholder or incomplete metadata:

• version and license are now required at the top level
• version must match the semantic-versioning pattern (^\d+\.\d+\.\d+(-[\w.-]+)?$)
• name must match the namespace/name (or nested) pattern
• parameter description rejects the literal "TODO: Add description" placeholder emitted by nextflow module spec

Why now

In nextflow-io/nextflow#7094 the nextflow module validate command starts validating meta.yml against this JSON schema. v1 of the schema is weaker than the existing hand-coded checks in Nextflow, so those checks have to stay in code as a layer on top. v1.1 is the first step toward letting Nextflow remove those duplicated checks: once v1.1 is published and Nextflow points its default at it, the remaining hand-coded rules in ModuleSpec.validate() can be deleted.

Test plan

Five fixtures live under module/v1.1/tests/ and pass Draft202012Validator as expected:

fixture	expected	what it covers
valid_spec.yml	pass	full spec with all required fields and patterns
invalid_missing_fields.yml	fail	missing version and license
invalid_name.yml	fail	name is a bare fastqc (no namespace)
invalid_version.yml	fail	version: v1.0 (not semver)
invalid_todo_description.yml	fail	parameter description: "TODO: Add description"

Open questions

• Branch name says v2 for historical reasons; the schema directory is v1.1. Happy to rename the branch if helpful.
• Should we also tighten paramSpec.description to reject any TODO:-prefixed string instead of just the exact placeholder?