📖 [Docs]: Add VS Code extension framework capability spec

[Marius Storhaug (MariusStorhaug)]

Adds a new VS Code Extension Framework capability to the central docs hub — the VS Code counterpart to Process-PSModule: one opt-in, GitHub-native pipeline that builds, tests, versions, packages, and publishes an extension from a template and a single settings file.

What is here

• Spec (spec.md) — the why/what: premise, principles, scope with an applicability test, normative requirements (MUST/SHOULD), and success criteria.
• Design (design.md) — the how: the find-version → build → test → release DAG, the built-once/shipped-once contract, host-matrix testing on a real editor, label-driven versioning, VSIX-to-GitHub-Release distribution (with optional marketplace publish), the configuration surface, and the template repo layout.
• index.md for the capability, plus nav wiring in zensical.toml and the regenerated Capabilities/index.md row.

Grounding

• Modelled on Process-PSModule — template + reusable workflow + single settings file, full lifecycle, label-driven SemVer.
• Design grounded in radical-ai-vscode's CI — the DAG, built-once/shipped-once, VSIX as a GitHub Release asset + install scripts, tagging via the Releases API (least privilege; GHEC-DR-safe).
• Rests on the MSXOrg Principles (Everything as Code, Decision before change, Extensible by default, Least-privilege).
• Reuses Release Management, Dependency Updates, and Merge Automation rather than redefining them.

No internal/user split

The framework itself is documented centrally here; each extension's own user docs live in that extension's repository.

Validation

• Index -Check clean (no drift)
• markdownlint: 0 errors
• documentation link checker: all links resolve

[Copilot]

Pull request overview

Adds a new VS Code Extension Framework capability to the docs hub, defining the spec (requirements) and design (pipeline shape and operational model) for an opt-in, GitHub-native build/test/version/release workflow for VS Code extensions, and wires it into site navigation and the Capabilities index.

Changes:

• Adds a new capability section with index.md, spec.md, and design.md under Capabilities/vscode-extension-framework/.
• Wires the new capability into site navigation (zensical.toml) and the Capabilities index table.
• Documents the end-to-end lifecycle contract (built-once/shipped-once), host-matrix testing, label-driven SemVer, and GitHub Release–based VSIX distribution (optional marketplace).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/zensical.toml	Adds the new capability entry to the Capabilities navigation tree (index/spec/design).
src/docs/Capabilities/vscode-extension-framework/index.md	Introduces the capability landing page with the generated local index table.
src/docs/Capabilities/vscode-extension-framework/spec.md	Defines scope, normative requirements (MUST/SHOULD), and success criteria for the framework.
src/docs/Capabilities/vscode-extension-framework/design.md	Describes the implementation approach (DAG stages, built-once contract, versioning, publishing/distribution, least-privilege).
src/docs/Capabilities/index.md	Adds the new capability row to the generated Capabilities index table.