(docs) standard doc set and roadmap

[w1ck3ds0d4]

• Status: release, path to v1.0.0 (unchanged, restated in the standard ROADMAP.md shape)
• Added CLAUDE.md (repo commands, layout, conventions)
• Rewrote ROADMAP.md into the standard Now/Next/Later/Ideas/Done shape, carrying over all open v1 checklist items and milestones from the previous version, nothing re-scoped
• CHANGELOG.md, SECURITY.md, ARCHITECTURE.md, HOW_IT_WORKS.md, COMMERCIAL.md already existed and were left as is
• CONTRIBUTING.md skipped: no house template exists yet in BlueFlame to model it on (Daniel to confirm whether one should be written)

Now items (verbatim):

• Document the input matrix
• Document the secret matrix
• Consumer install template
• Version pinning policy
• Consumer smoke fixture
• Tag v1.0.0 and list on Marketplace (Daniel)