feat: support merging frontmatter with tp.file.include

[AndyEveritt]

Same as #1643 but changed the backwards compatibility of current_functions_object to be identical to previous behaviour

[Copilot]

Pull request overview

This PR adds support for merging frontmatter when using tp.file.include, enabling nested templates to contribute their frontmatter to the final output. This is a continuation of PR #1643 with improved backwards compatibility for current_functions_object.

Changes:

• Adds frontmatter tracking and merging throughout the template parsing pipeline
• Refactors internal functions to use a stack-based approach for function object management
• Implements frontmatter extraction and merging for included templates

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/core/Templater.ts	Adds frontmatter field to RunningConfig, implements function object stack management, and integrates frontmatter merging into template parsing and file operations
src/core/functions/internal_functions/file/InternalModuleFile.ts	Modifies generate_include to extract and merge frontmatter from included files, returning only content without frontmatter
src/core/functions/internal_functions/InternalFunctions.ts	Refactors module lifecycle to create new module instances per template parse instead of reusing them, enabling proper per-template state management
tests/main.test.ts	Updates test configuration to include the new required frontmatter field
docs/documentation.toml	Updates documentation for tp.file.include to describe the frontmatter merging behavior

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[Fred-Vatin]

Is there any obstacles preventing this PR to be finally merged ?

[AndyEveritt]

I'm not sure why it isn't being merged tbh. I've made a release so you can just install that in your Obsidian repo if you want to use it.
https://github.com/AndyEveritt/Templater/releases/tag/2.18.1-1698

It's what I've been doing since September and it has been working fine for me on desktop and mobile

[Zachatoo]

I did a test with the example from #1695 and it still isn't working with your changes, I get an empty object instead of a populated functions object and it fails.