Stabilize onboarding cycle UX and enforce Python 3.10+ runtime gates

[AreteDriver]

Why this PR

Argus currently mixes UX improvements, runtime compatibility guardrails, and CI/tooling updates. This draft groups them so reviewers can validate end-to-end onboarding behavior and Python baseline enforcement in one pass.

Scope

• Onboarding + cycle UX updates across main window, tabs, and cycle controller.
• Runtime hardening: fail fast when Python is below 3.10 before Qt initialization.
• Installer/launcher + docs/metadata alignment to a Python 3.10+ floor.
• Dev install reliability fix on Python 3.12.
• AI quality-gate and CI consistency updates.
• Restore merge-dropped auto-discovery lifecycle and four-tab navigation behavior.
• Make the production type gate actionable and eliminate its source-tree errors.
• Repair Linux Qt prerequisites and move the test stack to advisory-fixed compatible versions.

Commit map

• 1927368 onboarding/cycle workflow improvements.
• a60e321 test/config fallback hardening.
• 3129e1e AI tooling + changed-file quality gate.
• 73db298 docs/runtime baseline + CI typecheck alignment.
• e5a326f pre-Qt Python version guard.
• 5ec22e6 enforce Python floor in run.sh and install.sh.
• 6eee4b0 dev dependency conflict fix for fresh installs.
• d4e6377 restore onboarding lifecycle, repair import signal wiring, and unblock lint/type gates.
• 1b6d11d add AI-gate Qt packages, repair the Pillow resampling test, and upgrade pytest/pytest-asyncio.

Reviewer focus

• Unsupported interpreter path shows a clean error and exits before Qt app init.
• Auto-discovery connects once, respects settings, and disconnects on shutdown.
• Import paths share frame wiring for activation, removal, focus, and retry signals.
• Roster and cycle-control navigation land in the Fleet and Layouts containers.
• Python floor messaging is consistent across docs, scripts, and CI.
• CI type-checks production code rather than conflating source errors with test mocks.
• The pytest 9.0.3 / pytest-asyncio 1.4.0 pairing remains compatible across Python 3.10–3.12.

Validation evidence

• ruff check .: pass.
• ruff format --check .: 132 files formatted.
• mypy src/argus_overview --ignore-missing-imports --no-error-summary: pass locally and on GitHub.
• Focused onboarding/main-window suite: 132 passed.
• Changed-file suite: 804 passed, 3 skipped.
• Final pytest 9 UI/command/Windows regression suite: 913 passed, 3 skipped.
• Command-center API-preservation follow-up: 61 passed.
• pip-audit --ignore-vuln CVE-2026-3219: no known vulnerabilities after upgrading pip in the validation environment.
• bash -n install.sh run.sh: pass.
• Workflow YAML parse and git diff --check: pass.
• Fresh-head GitHub evidence before 1b6d11d: lint, format, mypy, secret scan, CodeQL, Truth Baseline, Linux package build, and normal security scan passed. Remaining failures were traced to missing AI-gate Qt packages, one stale Pillow assertion, and PYSEC-2026-1845 on pytest 8.4.2; 1b6d11d addresses exactly those causes.

Risk and rollout

• Behavior change is intentional for Python <3.10 users (now fast-fail).
• Workflow changes require maintainer review because the typecheck target is now the production package.
• Keep as draft until all fresh checks on head 1b6d11d are green and one reviewer validates the onboarding flow.

[gemini-code-assist]

Code Review

This pull request upgrades the project's minimum Python requirement to 3.10 and introduces several architectural and UX improvements. Key changes include the addition of a centralized CycleController for window management, an onboarding panel for the Overview tab, and enhanced character management with auto-discovery batching. Developer experience is also improved through pinned dependencies and pre-commit hooks. Review feedback suggests improving encapsulation in the CycleController by avoiding protected member access and refactoring the configuration directory resolution to prevent potential crashes in restricted environments.