Store processing diagnostics on task instead of includeProcessor during file loading

[Copilot]

Processing diagnostics are now accumulated on tasks during file loading rather than directly added to includeProcessor. The includeProcessor is created locally in getProcessedFiles() where task diagnostics are consolidated.

Changes

• resolveTypeReferenceDirectives(): Append unresolved reference diagnostics to task.processingDiagnostics instead of calling includeProcessor.addProcessingDiagnostic()
• parseTask.load(): Append lib reference diagnostics to task.processingDiagnostics instead of calling includeProcessor.addProcessingDiagnostic()
• fileLoader: Remove includeProcessor field
• getProcessedFiles(): Create local includeProcessor variable and pass it to addIncludeReason() instead of accessing via loader

// Before
p.includeProcessor.addProcessingDiagnostic(&processingDiagnostic{
    kind: processingDiagnosticKindUnknownReference,
    data: includeReason,
})

// After
t.processingDiagnostics = append(t.processingDiagnostics, &processingDiagnostic{
    kind: processingDiagnosticKindUnknownReference,
    data: includeReason,
})

This maintains task-level diagnostic ownership during parsing and consolidates them only when assembling the final processedFiles result.

Original prompt

Instead of using includeProcessor.addProcessingDiagnostic from resolveTypeReferenceDirectives store it on task

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[Copilot]

Pull request overview

This PR refactors how processing diagnostics are collected during file loading by storing them on individual tasks rather than directly on a shared includeProcessor instance. The includeProcessor is now created locally when needed and populated from task diagnostics.

Key Changes

• Processing diagnostics are accumulated on parseTask instances during file loading
• includeProcessor is created locally in getProcessedFiles() where task diagnostics are consolidated
• The fileLoader no longer maintains an includeProcessor field

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
internal/compiler/fileloader.go	Removed includeProcessor field from fileLoader struct and updated resolveTypeReferenceDirectives() to append diagnostics to task instead
internal/compiler/filesparser.go	Updated parseTask.load() to store diagnostics on task, created local includeProcessor in getProcessedFiles(), and updated addIncludeReason() to accept includeProcessor parameter