Ruby: Analyze and resolve Action View render calls

[marcoroth]

This pull request introduces ActionView render call analysis, a system that statically traces render calls across ERB templates to build dependency graphs, detect unresolved partials, find unused partials, and verify full resolvability of entry points.

Motivation

Herb needs to understand the render dependencies between templates to support runtime reactivity, Herb dev server patches, and for potential compile-time optimizations.

When a partial changes (whether its file on disk during development or its underlying state at runtime) we need to know which entry points are affected and may need re-rendering. The render graph gives us that reverse lookup, enabling the dev server to notify the right clients and future reactive rendering to trace exactly which templates to update.

Beyond reactivity, static resolution of render calls is a prerequisite for compile-time partial inlining (see #654). If we can prove at compile time that a render call resolves unambiguously to a single partial file, we can eliminate the expensive runtime file lookup entirely either by inlining the partial's content directly or by rewriting the call to ActionView's internal compiled method.

The fully_resolvable? API provides exactly that guarantee: it walks the full render tree and confirms there are no dynamic or unresolved gaps that would make such optimizations unsafe.

Example Output

bundle exec herb actionview graph app/views/profiles/show.html.erb

bundle exec herb actionview graph app/views/profiles/_header.html.erb

bundle exec herb actionview check

Ruby API

analyzer = Herb::ActionView::RenderAnalyzer.new("/path/to/project")

result = analyzer.analyze
result.unresolved  
result.unused    
result.issues?  

analyzer.fully_resolvable?("app/views/posts/show.html.erb") # => true/false

[pkg-pr-new]

npx https://pkg.pr.new/@herb-tools/formatter@1663

npx https://pkg.pr.new/@herb-tools/language-server@1663

npx https://pkg.pr.new/@herb-tools/linter@1663

commit: fa509f6

[github-actions]

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