Add standalone Nucleus integration

[jhlagado]

Summary

• register .nu as a first-class Debug80 source language
• discover and configure Nucleus targets beside AZM and Glimmer targets
• build through the standalone nucleus command while retaining canonical NOBJ and launchable Intel HEX
• translate exact Nucleus diagnostics into Debug80 diagnostics
• require an explicit target profile with real service destinations
• publish NOBJ and HEX as one recoverable artifact generation, rejecting stale or empty compiler output

Repository boundary

Nucleus now lives in the public GPL repository at https://github.com/jhlagado/nucleus. This integration deliberately keeps the existing in-tree copy until the runtime and compiler packages, real machine profiles, documentation sync, and source-map work are independently complete.

Validation

• Debug80 ordinary tests: 941 passed, 1 skipped
• Debug80 webview tests: 297 passed, 1 skipped
• focused Nucleus integration tests: 50 passed
• extension typecheck and build passed
• formatting and git diff --check passed
• standalone Nucleus adversarial review and 76-test suite passed

Source-level Nucleus stepping remains deferred until a D8-compatible source-map sidecar exists.

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[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Use Nucleus's actual line-comment delimiter

When a user invokes Toggle Line Comment, this configuration inserts #, which the compiler rejects: packages/nucleus/docs/specification.md defines // as the sole comment form and identifies hash as invalid syntax. The new TextMate grammar likewise matches #.*$, so valid // comments are not highlighted while invalid text is. Update both the language configuration and grammar to recognize //.

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