Wist 0.1.0-alpha.3 runtime-boundary and release-gate hardening

This release supersedes the locally built 0.1.0-alpha.2 artifact. The version was advanced because the package bytes and observable runtime contracts changed.

Runtime fixes

• one-shot execution no longer leaves a prepared session in AsyncLocal;
• disposed engines release their host and collectible runtime boundary;
• RealNumberImpl is normalized before generic result casting, including object;
• CLR numeric arguments and delegate signatures adapt to NumbersModule runtime types;
• exact user-defined conversions bridge NumbersModule values and trusted CLR calls on both backends.

Release verification

• exact timeout-bounded TRX contract;
• actual public API snapshot diff against the retained baseline;
• exact compiler/runtime assembly payload comparison;
• reviewed preset and manifest SHA-256 values;
• seeded test-count, API, package identity and preset-semantic mutants;
• clean package consumers and incompatible-checkout rejection.