Completes the Phase 1 runner and migrates the 11 test files onto it.
- forward-declare the registry accessors in the test preamble; they are
defined at the end of the unit but the El runner is compiled in between
- eltest.el: explicit trailing return in the void emit_* helpers, which
otherwise lower to 'return println(...)' and fail to compile
- test files import runtime/eltest.el explicitly, using the language's own
textual import mechanism rather than compiler-side auto-injection
- DESIGN.md 6.5: gate on allocation COUNT AND BYTES, not count alone
Verified: self-hosting fixpoint byte-identical (gen2 == gen3). 6 of 11
suites run and report per-test timing. The other 5 fail to COMPILE, and
fail identically under the committed compiler -- pre-existing breakage
this framework makes visible for the first time.
Neuron