docs: define ECLI extensions layer architecture

[SSobol77]

Defines the ECLI Extensions Layer architecture contract for v0.3.0.

Scope:

• documents src/ecli/extensions as the only approved imported extension asset path
• defines imported upstream assets as read-only from the ECLI integration perspective
• documents deterministic adapter-only integration
• forbids VS Code extension host, Node activation, Copilot runtime activation, hidden command execution, and generic PTY terminal reintroduction
• preserves F11 as the PySH Console Panel
• documents package-data and release-contract impact for future extension asset import
• updates agent/tooling contracts for AGENTS, CLAUDE, CODEX, .claude, and .codex
• records that VMLab moved to v0.3.5 and is blocked until v0.3.0 Extensions Foundation is complete

Validation:

• uv run ruff check src tests
• uv run ruff format --check src tests
• uv run pytest -q tests/docs tests/packaging tests/ui/test_terminal_panel_reservation.py tests/ui/test_pysh_console_panel.py tests/ui/test_pysh_console_panel_keybindings.py

No source/runtime changes.
No src/ecli/extensions asset import.
No VMLab implementation changes.

Summary by CodeRabbit

Release Notes

• Documentation

  • Established Extensions Layer architecture contract defining rules for imported extension assets and deterministic adapter code.
  • Clarified project milestone structure: Extensions Foundation foundation (v0.3.0) precedes VMLab Skeleton (v0.3.5).
  • Added packaging expectations for future extension asset inclusion in wheel/sdist distributions.

• Chores

  • Updated release planning documentation; no functional changes.
  • F11 remains dedicated to PySH Console Panel.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: ASSERTIVE

Plan: Pro

Run ID: 4c9b0b12-dee7-45c8-9b2b-e34211f74d23

📥 Commits

Reviewing files that changed from the base of the PR and between fa03c78 and 84af391.

📒 Files selected for processing (13)

• .claude/PIPELINE.md
• .claude/project-context.md
• .codex/PIPELINE.md
• AGENTS.md
• CLAUDE.md
• CODEX.md
• docs/architecture/README-architecture.md
• docs/architecture/extensions-layer.md
• docs/architecture/panel-console-stabilization.md
• docs/product/terminology-and-naming.md
• docs/release/build-matrix.md
• docs/release/packaging-flows.md
• docs/release/release-checklist.md

---

📝 Walkthrough

Walkthrough

This PR establishes the normative ECLI Extensions Layer contract for the v0.3.0 Foundation milestone. It creates docs/architecture/extensions-layer.md as the authoritative contract, propagates rules into architecture/terminology/release docs, injects the contract into all AI agent instruction files (AGENTS.md, CLAUDE.md, CODEX.md, and their .claude/.codex counterparts), and moves the VMLab Skeleton milestone to v0.3.5.

Changes

Extensions Layer Contract (v0.3.0 Foundation)

Layer / File(s)	Summary
Normative contract document docs/architecture/extensions-layer.md	Creates the full architecture contract defining the Extensions Layer boundary (src/ecli/extensions/), asset immutability, deterministic adapter responsibilities, supported data-only input types, forbidden runtime behaviors, PySH boundary, packaging impact for #98/#99, issue #97–#105 sequencing, and the issue #97 acceptance checklist.
Architecture index, terminology, and panel-stabilization cross-references docs/architecture/README-architecture.md, docs/product/terminology-and-naming.md, docs/architecture/panel-console-stabilization.md	Registers extensions-layer.md in the Architecture-Internal Authority Map, adds canonical Extensions Layer Terminology with prohibited alternative naming, and updates the panel-console-stabilization release boundary with a VMLab milestone renumbering clarification while preserving F11/PTY guidance.
Release packaging docs and checklist docs/release/build-matrix.md, docs/release/packaging-flows.md, docs/release/release-checklist.md	Adds planned packaging rules specifying wheel/sdist inclusion for non-.py extension assets, read-only shipping constraints, required packaging tests, and confirms the 21-asset GitHub Release count remains unchanged.
AI agent instruction files AGENTS.md, CLAUDE.md, CODEX.md, .claude/project-context.md, .codex/PIPELINE.md	Injects the Extensions Layer contract into all AI agent instruction files covering approved asset location, read-only upstream handling, deterministic adapter requirement, prohibited runtime/activation/network behaviors, F11 preservation, PTY emulator ban, import sequencing by issue number, and VMLab scope gating.
VMLab milestone and pipeline gating .claude/PIPELINE.md	Updates issue #54 milestone from v0.3.0 to v0.3.5, adding text clarifying VMLab Skeleton remains status:blocked until the v0.3.0 Extensions Foundation milestone completes.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related issues

• arch: define ECLI Extensions Layer under src/ecli/extensions #97: This PR directly implements issue #97 by creating docs/architecture/extensions-layer.md as the normative contract, updating all AI agent instruction files with the Extensions Layer contract, defining imported assets as read-only, and moving VMLab to v0.3.5 as specified.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title directly and clearly summarizes the main change: adding architecture documentation for the ECLI extensions layer.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch issue/97-extensions-layer-architecture

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud