docs: delete ECHO-CNO-BRIDGE-SUMMARY.md (overclaimed proofs)

The summary asserted as proven two theorems that do not exist in
the codebase:

  * cno-thermodynamic-optimality  — claimed:
      ∀ s T → fiber-energy cno-identity s T ≡ zero
    Reality: only the trivial T=0 case is proven
    (cno-zero-energy-at-zero in EchoThermodynamics.agda).
    EchoThermodynamics.agda's own comment notes:
    "The stronger claim 'CNOs dissipate zero energy at every
    temperature' is not yet discharged — it needs FiberSize to
    track actual preimages."

  * cno-information-preservation  — references function
    `echo-information-loss` that is not defined anywhere in the
    codebase.

Other inflated framing in the same file: "Production Ready",
"100% test coverage", "Statistical Mechanics Module" (does not
exist), thermodynamic-bridge stability "90/100".

Matches the inflated-narrative pattern flagged in the
auto-memory's gemini-content-audit guidance. Removing the file
rather than rewriting it because the conceptual content is
already covered (more honestly) in the canonical
docs/ECHO-CNO-BRIDGE.adoc — which itself still needs a sweep
for the same overclaims (separately scoped).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath