[SaridakisStamatisChristos]

Summary

Performs a professional productization cleanup without changing CharterOS runtime semantics.

Product-facing cleanup

• rewrites the README around the current aviation charter operating platform rather than implementation chronology;
• adds a current charter lifecycle / booking flow diagram and tightens authority-boundary language;
• corrects the README's branch-protection wording while preserving the actual CI/provenance claims;
• replaces chronology-named assurance documents with evergreen engineering assurance maps;
• updates the documentation index and critical-flow reading paths;
• preserves ADRs and durable aviation/security/recovery/provenance evidence.

Repository naming cleanup

• renames PR-numbered unit/integration test files to capability-oriented names without changing their blobs;
• replaces PR-numbered CI scratch paths with semantic CharterOS names;
• adds a repository-hygiene regression test for development-era path/prose/test-identifier leakage.

Boundaries

• no algorithmic or runtime behavior changes are intended;
• no CI, security, integrity, correctness or dependency controls are weakened;
• no release or tag is created;
• proprietary licensing remains unchanged.

Full CI is the merge gate. Any residue or regression surfaced by the new hygiene test or existing verification suite will be repaired on this PR before merge.