docs(readme): rewrite README around the control-plane + MAPE-K self-* framing (must pass claims:check)

[williamzujkowski]

Part of #3858. Depends on #3826 (claims:check), #3838 (entry-point docs).

Context

The rewrite: descriptor, control-plane metaphor table (scheduler/admission control/event log/data plane), self-* sections each tracing to a real mechanism, 'What this is NOT' preserved+updated. EVERY new substantive claim enters the claims registry in the SAME PR; claims:check blocks drift.

Acceptance criteria

• README restructured; descriptor updated; auto-generated sections (tool tables, counts) untouched as generated
• All new claims registered with evidence; claims:check green
• 'What this is NOT' present, accurate
• Self-* table: each row cites the implementing module (doctor / ResilientAdapter circuit-breaker / LinUCB+TOPSIS / trust tiers+ClawGuard+sandbox)

Evidence required

claims:check + all docs gates green.

Out of scope

Docs-tree IA (next child); website.