Parser: Introduce RubyParameterNode and support block arguments

[marcoroth]

This pull request adds block argument extraction to both ERBBlockNode and ERBRenderNode, refactors the render node structure, and unifies parameter representation across the parser.

We renamed RubyStrictLocalNode → RubyParameterNode to we can reuase the existing nodes from the strict locals for both ERBBlockNode and ERBRenderNode.

Now shared by both strict locals and block arguments. Added keyword, splat, and block booleans to distinguish all parameter types:

@ RubyParameterNode
├── name: "component"
├── default_value: ∅
├── kind: "positional"
└── required: true

<% items.each_with_index do |item, index| %>
  <%= item %>
<% end %>

@ ERBBlockNode
├── content: " items.each_with_index do |item, index| "
├── body: [...]
├── block_arguments: (2 items)
│   ├── @ RubyParameterNode (name: "item", required: true)
│   └── @ RubyParameterNode (name: "index", required: true)
└── end_node: ...

Follow up on #1583

[pkg-pr-new]

npx https://pkg.pr.new/@herb-tools/formatter@1585

npx https://pkg.pr.new/@herb-tools/language-server@1585

npx https://pkg.pr.new/@herb-tools/linter@1585

commit: 642d0a8

[github-actions]

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