Reorganize documentation and project governance

[miuchan]

Summary

• rewrite the repository and locale landing pages around current verified capabilities, the active frontier, quick start, task-based navigation, and honest maturity/licensing boundaries
• reorganize the multilingual documentation hub into a goal-oriented map while preserving canonical machine-facing research records
• add current snapshots to all research-status pages and update architecture/scope pages with the generated-hammock Dwyer--Kan and terminating-reduction results
• expand the contribution workflow with proof, model, documentation, validation, and PR policies
• add canonical and four-language governance/security policies
• add pull-request, bug-report, and research-proposal GitHub templates
• extend documentation validation to require governance/security mirrors and canonical project-health files

Verification

• parsed every issue-form YAML file successfully
• ./scripts/check-doc-locales.sh
• ./scripts/check-source-quality.sh
• git diff --check
• ./scripts/quality-gate.sh (3664 Lean targets, declaration lint, executable examples, and axiom allowlist all passed)

Important boundary

No open-source license is present or selected. This change makes that boundary prominent and does not claim that public source visibility grants reuse rights. Choosing a license remains an explicit maintainer/legal decision outside this documentation reorganization.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

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